Cells contain chromosomes, structures where all of our genetic material resides. Most human beings have a total of 46 chromosomes, or 23 pairs. Genetic material is called DNA (deoxyribonucleic acid). DNA sequences make up genes. Genes produce proteins that make our cells work properly. We inherit our DNA from our parents, where half of our DNA is paternal in origin and half of our DNA is maternal in origin. Therefore, there are two copies of every gene: a maternal copy and a paternal copy (and hence a maternal copy of every chromosomes and a paternal copy of every chromosome). An embryo receives the maternal and paternal copy of every gene through the egg and sperm, respectively, at conception.
For example, Cystic Fibrosis (CF) is a common genetic disorder that primarily affects the lungs of affected patients. An alteration in the DNA sequence, or a mutation, in a specific gene alters the function or availability of the resulting protein. This leads to a build up of mucus within the lungs, lung dysfunction and possible death. Genetic disease is caused by abnormalities of gene function.
This can occur by having:
• Aneuploidy - too many or too few chromosomes
• Translocation - when chromosome segments have changed location
• Single gene change -
o Inversion: a reversal of part of a chromosome
o Point mutation: a change in the sequence of DNA
Frame shift mutation: a type of point mutation which alters the construct of the final protein
o Deletion: a loss of part or all of a gene
o Insertion: an addition of genetic material to the sequence of DNA
Duplication: a type of insertion where the added genetic material is a specific sequence of DNA that has doubled
Repeat expansion: type of insertion where the added genetic material is a specific sequence of DNA that has multiplied several times in tandem
In 1967, Edwards and Gardner reported the successful sexing of rabbit blastocysts. This first report of PGD was published in Nature in 1967, but it was not until the 1980s that human IVF was fully developed, which coincided with the breakthrough of the highly sensitive polymerase chain reaction (PCR) technology. Handyside and collaborators' first successful attempts at testing were in October 1989 with the first births in 1990. In these first cases, PCR was used for sex determination of embryos for patients carrying X-linked diseases.
Who should be considered to have a PGD?
• Women of advanced maternal age (over 35)
• Couples with recurrent miscarriages
• Couples who have experienced several failed IVF cycles
• Couples who have had a prior pregnancy with a chromosome abnormality
• Men with infertility requiring intracytoplasmic sperm injection (ICSI)
• Men with positive aneuploidy sperm screening
• Couples where at least one partner is has aneuploidy mosaicism
• Couples where at least on partner is a carrier of an X-linked disease
• Couples where at least one partner is a carrier of a structural chromosomal rearrangement
These indications can be categorized differently as:
• PGD for single gene mutations
• PGD for determination of chromosome number (aneuploidy)
• PGD for structural chromosome abnormalities (translocations)
• PGD for Tissue Typing
• PGD for Gender Selection
PGD for single gene disorders
IVF with PGD represents a major scientific advance for couples known to be at risk for having a child with inherited genetic disease.
This can be a monogenic disorder, meaning the condition is due to a single gene only, like:
• Autosomal Dominant Mutations: A mutation in one copy of the gene (maternal copy or paternal copy) is sufficient to cause disease. An affected individual has a 50% chance of passing down the mutated copy and a 50% chance of passing down the non-mutated copy. If the mutated copy is passed down, the embryo and resulting child is predicted to be affected with the genetic disorder.
• Autosomal Recessive Mutations: A mutation in both copies of the gene (maternal copy and paternal copy) is necessary to cause disease. A mutation in copy of the gene renders one an “unaffected carrier”. If a mutated copy is passed down from each parent, the embryo and resulting child is predicted to be affected with the genetic disorder.
• X-linked Recessive: Mutations on the X chromosome are more likely to cause disease in men than in women, since women have a second X chromosome that acts like a “protective factor”.
Prevalence of some single gene disorders
(Values are for liveborn infants)
Familial hypercholesterolemia 1 in 500
Polycystic kidney disease 1 in 1250
Huntington disease 1 in 2,500
Hereditary spherocytosis 1 in 5,000
Marfan syndrome 1 in 20,000
Sickle cell anemia 1 in 625
Cystic fibrosis 1 in 2,000
Tay-Sachs disease 1 in 3,000
Phenylketonuria 1 in 12,000
Mucopolysacchridoses 1 in 25,000
Glycogen storage diseases 1 in 50,000
Galactosemia 1 in 57,000
Duchenne muscular dystrophy 1 in 7,000
Hemophilia 1 in 10,000
PGD can serve to diagnose late-onset diseases and (cancer) predisposition syndromes
Family studies have revealed that some types of cancers are heredity. People with a mutation in specific gene are pre-disposed to an increased risk of developing cancer during their lifetime. One example of a hereditary cancer syndrome is Hereditary Breast and Ovarian Cancer (HBOC) that is linked to two genes: BRCA1 (on chromosome 17) and BRCA2 (on chromosome 13). By using PGD, prospective parents who have an identified mutation in BRCA1 or BRCA2 can choose to have embryos that are free of the familial mutation for embryo transfer. Children born without the identified familial mutation are at no greater risk than the general population to having cancer. Cancers for which PGD has been performed:
Breast / Ovarian cancer BRCA1, BRCA2
Familial adenomatous polyposis APC
Gorlin syndrome PTCH
Hereditary nonpolyposis colorectal cancer MLH1, MSH2, MSH6, PMS2
LH-Fraumeni syndrome TP53
Multiple endocrine neoplasia Type 2a RET
Neurofibromatosis 1 NF1
Neurofibromatosis 2 NF2 / merlin
Rhabdoid predisposition syndrome hsnF5
Tuberous sclerosis complex TSC1, TSC2
Von Hippel-Lindau disease VHL
Source: JAMA, December 13, 2006—Vol 296, No. 22
PGD for determination of chromosome structure
A balanced translocation is an exchange of genes between chromosomes without any net gain or loss in genetic material. Usually, translocation carriers do not face any mental or physical disabilities; however, they are at an increased risk for implantation failure, recurrent pregnancy loss, or mental or physical problems in offspring (if the translocation is passed on in the unbalanced form).
PGD for determination of chromosome number
(also known as aneuploidy testing)
As mentioned above, most humans have 46 chromosomes which can be arranged into 23 pairs. Of the 23 pairs of chromosomes, one pair, the sex chromosomes, determine a person’s sex. Women have two copies of the X chromosomes, whereas, men have one copy of the X chromosome and one copy of the Y chromosome. During normal sex cell production, the resulting sperm and the oocyte should contain 23 chromosomes each. After fertilization, the embryo will have 23 chromosomes from each parent, or a total of 46.
The diagram showing the 46 chromosomes in a human cell arranged in pairs. The last 2 chromosomes are the chromosomes which determine the sex of an individual. If there is an X and a Y then it's the cell from a male, if there are two X's then it's a female. This cell therefore belongs to a male.
Sex cell production does not always lead to a sperm or oocyte with exactly 23 chromosomes. Misdivision can lead to an extra or missing chromosome in the sex cell, and hence in the resulting zygote. Certain chromosomes seem to be more prone to abnormal copy number than others. For example, an embryo is more likely to have an extra copy of chromosome 13, or chromosome 21 than an extra copy of chromosome 1 or 3.
A common type of aneuploidy is the presence of three copies of chromosome 21, or trisomy 21. Such an embryo would have a total of 47 chromosomes instead of 46. A child born with this abnormality is said to have Down syndrome. The picture below (www.reproductivegenetics.com) demonstrates the genetic test results of a cell that contains a normal number of chromosome 18 (2 copies) and an abnormal number of chromosome 21 (3 copies).
Blastomere analysis revealing three signals for chromosome 21, diagnosing the embryo with Trisomy 21, or Down syndrome
A missing sex chromosome, for example a zygote with only one X chromosome (and no Y chromosome), will often lead to a spontaneous abortion but can also result in a live born child. A child born with this abnormality will look like a female and is said to have Turner Syndrome.
The main indications for this screening are:
• Advanced maternal age.
• History of recurrent miscarriages.
• Repeated unsuccessful implantation.
• Obstructive and non-obstructive azoospermia.
• Unexplained infertility
The estimated chances for a woman to deliver a child with an aneuploidy condition are as follows:
• At age 30 years - 1/385
• At age 35 years - 1/179
• At age 40 years - 1/63
• At age 45 years - 1/19
In general, if an embryo contains an extra or missing chromosome, there are three possible outcomes:
• The embryo will not implant and therefore will not produce a pregnancy.
• If the embryo implants, it will most likely end with a miscarriage.
• If the baby born, most probably it will end with birth defects.
A study published in 2008 in the journal Fertility and Sterility found that testing for the 9 chromosome that are most often abnormal in copy number decreases the chance for miscarriage by about 50%.
Decrease implantation ration related to increase aneuploidy
The estimated percentages of embryos that are affected with aneuploidy are as follows:
• For women between the ages of 35 to 39 years approximately 40% to 50% embryos are abnormal
• For women 40 years and older, on average, greater than 50-60%% of embryos are abnormal
Percent of Aneuploid oocytes in relation to maternal age. Analysis of 1551 cycles. The number on the graph present number of oocytes analyzed. (From Verlinsky and Kuliev, Clinical application of polar body biopsy. In: Gardener et al. Textbook of Assisted Reproduction Technologies. 3rd Ed. 2008 and www.reproductivegenetics.com)
Ethically challenging applications of PGD
Preferentially select female embryos to minimize the chance of having a child affected with an X-linked condition (such as hemophilia and fragile X syndrome).
Gender election can also be used by couples desiring a child of a specific sex.
Opinions on whether sex selection for non-medical reasons is acceptable differ widely.
PGD for Human Leukocyte Antigen tissue typing
Human Leukocyte Antigen (HLA) tissue typing or tissue matching is an additional application of PGD to determine if an embryo could lead to the birth of a child who is a tissue match for an ill sibling that could benefit from a transplant of HLA matched cells (such as in the case of bone marrow transplant for leukemia). This raises many ethical and social questions, including:
1. Whether an embryo should be ruled out or ruled in based solely on it’s HLA make type (non-transferred embryos are not being selected against due to a specific disease)
2. Whether a child should be born on the basis that he or she may be the source of life saving therapies for a sibling
Technical aspects of preimplantation genetic diagnosis
By definition, PGD is performed prior to implantation. Embryos are kept in a safe culture until the genetic test results are obtained. The testing can be carried out using several techniques, depending on the nature of the studied condition, and on various cell types. Generally, PCR-based methods are used for monogenic disorders (and HLA typing) and FISH for chromosomal abnormalities (including sex determination).
The biological material that is the source of DNA to be tested can be one of three types of cells. A biopsy procedure can take place to obtain the necessary cells. Biopsy can be performed on:
• Unfertilized and fertilized oocytes (for polar body cells, or PBs)
• On day three cleavage-stage embryos (for blastomere cells)
• On blastocysts (for trophectoderm cells)
The biopsy procedure always involves two steps: the opening of the zona pellucida and the removal of the cell(s). There are different approaches to opening the zona pellucida: mechanical, chemical (Tyrode’s acidic solution) and laser technology. Addtionally, there are several ways to obtain the necessary cells: extrusion method or aspiration method for the removal of PBs and blastomeres, and herniation method for the removal of trophectoderm cells.
Polar body biopsy
The polar bodies have no known function except to assist in cell division. They are simply “by-products” of the egg’s division. Once implantation occurs, the polar bodies disintegrate and are not part of the developing fetus. During normal ovulation, An oocyte divides into two unequally sized cells: the larger cell is the primary oocyte, the smaller cell is the first polar body. Upon penetration of the primary oocyte by the sperm (fertilization), but prior to the joining of the sperm’s genetic material with the egg’s genetic material, the oocyte undergoes another cell division, producing two unequally sized cells. The genetic material of the larger cell will join with the sperm’s genetic material to create the pre-embryo, and the smaller cell is called the second polar body.
The PBs can be removed and tested for their genetic content to identify what the oocyte has released. This helps to infer what the oocyte has retained. Polar body analysis only evaluates the female’s genetic contribution, since PBs are by-products of egg production. For example: if the PBs contain too few chromosomes, the oocyte might have retained an extra chromosome, leading to aneuploidy in the resulting embryo. Or, if the PBs are found to have the copy of the gene that is mutated, the oocyte most likely has retained a copy of the gene that is not mutated, and hence, can be considered for embryo transfer.
PB analysis has been used for diagnosing translocations, monogenic disorders of maternal origin, as well as aneuploidy (www.reproductivegenetics.com).
Biopsy of the first polar body (www.reproductivegenetics.com)
Polar body with a normal result for chromosomes 13 (red), 16 (blue), 18 (purple), 21 (green) and 22 (yellow) (www.reproductivegenetics.com). Following the diagnostic procedure, the egg can be assessed as suitable for fertilization.
Blastomere biopsy is usually performed the morning of day three post-fertilization (62 – 64 hours post insemination), when normally developing embryos reach the eight-cell stage (each cell is called a blastomere). The biopsy is usually performed on embryos at an 8-cell or later stage of development. The main advantage of blastomere analysis over PB analysis is that the genetic contribution from both parents can be studied. The main disadvantage of blastomere analysis is that cleavage-stage embryos are found to have a high rate of chromosomal mosaicism. Mosaicism is the term given to a phenomenon where a single organism has cells with different genetic compositions (for example: some cells are normal and some cells have trisomy 21 or Down syndrome). Mosaicism can make PGD result interpretation difficult since we assume results obtained on one or two blastomeres will be representative for the rest of the embryo. It is for this reason that some programs utilize a combination of PB biopsy and blastomere biopsy.
Embryo biopsy for PGD (www.reproductivegenetics.com)
Blastocyst formation begins on day 5 post-egg retrieval and is defined by the presence of an inner cell mass and the outer cell mass or trophectoderm (TE cells). A hole is breached in the zona pellucida in a similar manner as described for a cleavage-stage embryo biopsy, and cells are removed from the trophectoderm using a fine biopsy pipette. The inner cell mass is left undisturbed. Genetic analysis is performed via FISH or PCR analysis as described below.
The chromosomal differences between the inner cell mass and the TE cells can reduce the accuracy of diagnosis; however, this mosaicism has been reported to be lower than in cleavage-stage embryos. The main disadvantage to performing this biopsy is the stage at which it is performed. Approximately half of all embryos will survive to the blastocyst stage. This can restrict the number of blastocysts available for biopsy, limiting in some cases the success of the PGD.
Genetic analysis techniques
Fluorescent in situ hybridization (FISH)
FISH is a cytogenetic technique that can be used to detect and localize the presence or absence of specific DNA sequences on chromosomes.
In contrast to karyotyping, it can be used on interphase chromosomes from PBs, blastomeres and TE samples. The cells are fixated on glass microscope slides and hybridized with DNA probes. Each of these probes is specific for part of a chromosome, and are labeled with a fluorochrome. Currently, a large panel of probes is available for different segments of all chromosomes, but the small number of different fluorochromes limits the number of chromosomes / signals that can be analyzed simultaneously.
The type and number of probes that are used on a sample depends on the indication. For sex determination probes for the X and Y chromosomes are applied along with probes for one or more of the autosomes as an internal FISH control. More probes can be added to check for aneuploidies, particularly those that could give rise to a viable pregnancy (such as a trisomy 21). The use of probes for chromosomes X, Y, 13, 14, 15, 16, 18, 21 and 22 has the potential of detecting 70% of the aneuploidies found in spontaneous abortions.
Polymerase chain reaction (PCR)
Polymerase chain reaction (PCR) was first conceived by Kary Mullis in 1985. PCR is used to obtain many copies of a particular stretch of the genome, making further analysis possible. It is a highly sensitive and specific technology, which makes it suitable for all kinds of genetic diagnosis, including PGD.
The precise diagnosis by PCR relies on several key elements: adequately functioning reagents, the presence of an adequate tested DNA template, and the lack of any DNA contamination. Specifically, PCR for PGD has three potential pitfalls:
• Amplification failure
• Allele dropout (ADO)
This can occurs in approximately 10% of isolated blastomeres, regardless of their genotype. The main reasons for amplification failure include biopsy technique, premature cell lysis, lysis protocol used, and sub-optimal PCR conditions
Allele Dropout (ADO)
This occurs when only one of the two alleles present in a cell is amplified to a detectable level. The causes of ADO are still not fully understood. Current hypotheses include inaccessibility of the DNA template due to imperfect denaturing temperature or incomplete cell lysis and DNA degradation prior to PCR.
This is one of the greatest obstacles PGD; there may be several sources for possible contamination:
• Spermatozoa are still embedded in the zona pellucida (can be prevented by ICSI)
• Second polar body or trophectoderm cells
• Maternal cumulus cells adherent to the oocytes
• External contamination either from laboratory technicians or from PCR products
Preimplantation genetic haplotyping
Preimplantation genetic haplotyping (PGH) is a new clinical method of Preimplantation genetic diagnosis (PGD). PGH is being developed at London's Guy's Hospital and greatly advances PGD by using DNA fingerprinting rather than identifying the actual genetic signature (such as point mutations).
Compared with previous PGD techniques, PGH allows for the confirmation of which copy of the gene was passed to an embryo by analyzing genetic markers that are upstream and downstream of the actual mutation site. This additional confirmation increases the accuracy of the result. PGH also allows for the testing of embryos for deletions, which cannot be detected with traditional direct mutation analysis. PGH is used when testing embryos for conditions such as Fragile X syndrome and Duchenne Muscular Dystrophy since these syndromes result from large deletions.
Concerns and Disadvantages
There are some disadvantages to PGD:
• Fertile couples must undergo IVF to produce suitable embryos
• Technical problems might occur during PB, blastomere, or TE biopsy/ preparation
• Even with a successful IVF and PGD procedure, pregnancy is not guaranteed after transfer, nor is a term or near-term delivery
• Analysis of a single cell has limitations and misdiagnosis resulting from mosaicism may occur (for this reason, prenatal diagnosis is recommended should pregnancy be achieved).
• Not all chromosome abnormalities can be diagnosed with PGD. Currently, FISH offers evaluation of less than half of the 23 chromosomes.
Current recommendations from the Society for Assisted Reproductive Technology (SART) and American Society for Reproductive Medicine (ASRM) state that available evidence does not support the use of PGD to improve live-birth rates for advanced maternal age, recurrent pregnancy loss, or implantation failure and recommends that patients be counseled about the limitations of the technique and should not make future treatment decisions based solely on PGD results.
To date, there are no reports of increased fetal malformation rates or other identifiable problems in babies born from IVF with PGD/PGS. The possible presentation of other rare abnormalities later in life as a consequence of the biopsy procedure should be continue to be investigated by follow up of children born after PGD. The few kids that are reaching their twenties now seem to be healthy.
Almost weekly reports on identification of genetic mutations associated with various diseases are published in scientific and lay literature. In the future, genetic links to common diseases (eg, diabetes, hypertension, cardiovascular diseases, endometriosis, and cancers) may be identified, and PGD will become available to limit the transmission of these genetic predispositions and disorders to future generations.
Although PGS has been incorporated into the care of patients undergoing IVF treatment, its indications, utility, and outcomes remain an active area of research and controversy in reproductive medicine. Using polar bodies biopsy and/or blastocyst biopsy are currently under investigation as a better alternatives to the day 3 blastomere biopsy only. As preimplantation screening for disorders optimizes, its place in medicine and society will continue to generate an ethical debate.
Genetic diseases transmittable to offspring that can be diagnosed by PGD after biopsy of the oocytes and embryos (www.reproductivegenetics.com):
ACYL-CoA DEHYDROGENASE, MEDIUM-CHAIN, DEFICIENCY
ACYL-CoA DEHYDROGENASE, VERY LONG-CHAIN; ACADVL
ADADENOSINE DEAMINASE DEFICIENCY; ADA
ADENOMATOUS POLYPOSIS OF THE COLON; APC
ALBINISM, OCULAR, TYPE I; OA1
ALOPECIA UNIVERSALIS CONGENITA; ALUNC
ALPERS DIFFUSE DEGENERATION OF CEREBRAL GRAY MATTER WITH HEPATIC CIRRHOSIS
ALPHA 1 ANTITRYPSIN DEFICIENCY (AAT)
ALPORT SYNDROME, X-LINKED; ATS
AMYLOIDOSIS I, HEREDITARY NEUROPATHIC
AMYOTROPHIC LATERAL SCLEROSIS 1; ALS1
ANDROGEN RECEPTOR; AR (testicular feminization; spinal and bulbar muscular atrophy; Kennedy disease)
ANEUPLOIDIES BY STR GENOTYPING
ANGIOEDEMA, HEREDITARY; HAE
BASAL CELL NEVUS SYNDROME; BCNS (GORLIN)
BETA-HYDROXYISOBUTYRYL CoA DEACYLASE, DEFICIENCY OF
BLEPHAROPHIMOSIS, PTOSIS, AND EPICANTHUS INVERSUS; BPES
BLOOD GROUP--KELL-CELLANO SYSTEM
BRACHYDACTYLY, TYPE B1; BDB1
BRAIN TUMOR, POSTERIOR FOSSA OF INFANCY, FAMILIAL
BREAST CANCER, FAMILIAL
BREAST-OVARIAN CANCER, FAMILIAL, SUSCEPTIBILITY TO
BRUTON AGAMMAGLOBULINEMIA TYROSINE KINASE; BTK
CARDIOENCEPHALOMYOPATHY, FATAL INFANTILE, DUE TO CYTOCHROME c OXIDASE DEFICIENCY
CARDIOMYOPATHY, FAMILIAL HYPERTROPHIC, 4; CMH4
CEROID LIPOFUSCINOSIS, NEURONAL 2, LATE INFANTILE; CLN2
CHARCOT-MARIE-TOOTH DISEASE, AXONAL, TYPE 2E
CHARCOT-MARIE-TOOTH DISEASE, DEMYELINATING, TYPE 1A; CMT1A
CHARCOT-MARIE-TOOTH DISEASE, DEMYELINATING, TYPE 1B; CMT1B
CHARCOT-MARIE-TOOTH DISEASE, X-LINKED, 1; CMTX1
CHOLESTASIS, PROGRESSIVE FAMILIAL INTRAHEPATIC 2
CHONDRODYSPLASIA PUNCTATA 1, X-LINKED RECESSIVE; CDPX1
COLLAGEN, TYPE IV, ALPHA-5; COL4A5
COLORECTAL CANCER, HEREDITARY NONPOLYPOSIS, TYPE 1; HNPCC1
COLORECTAL CANCER, HEREDITARY NONPOLYPOSIS, TYPE 2; HNPCC2
CONGENITAL ADRENAL HYPERPLASIA (CAH)
CRANIOFACIAL DYSOSTOSIS, TYPE I; (CFD1)
CUTIS LAXA, AUTOSOMAL RECESSIVE, TYPE I
CYSTIC FIBROSIS; CF
CYSTINOSIS, NEPHROPATHIC; CTNS
DARIER-WHITE DISEASE; DAR
DEAFNESS, NEUROSENSORY, AUTOSOMAL RECESSIVE 1; DFNB1
DIAMOND-BLACKFAN ANEMIA; DBA
DYSTROPHIA MYOTONICA 1
EARLY-ONSET FAMILIAL ALZHEIMER DISEASE;
ECTODERMAL DYSPLASIA 1, ANHIDROTIC; ED1
ECTODERMAL DYSPLASIA, ANHIDROTIC
ECTRODACTYLY, ECTODERMAL DYSPLASIA, AND CLEFT LIP/PALATE SYNDROME 1; EEC1
EHLERS-DANLOS SYNDROME, TYPE VI
EMERY-DREIFUSS MUSCULAR DYSTROPHY, AUTOSOMAL RECESSIVE; EDMD3
EMERY-DREIFUSS MUSCULAR DYSTROPHY, X-LINKED; EDMD
EPIDERMOLYSIS BULLOSA DYSTROPHICA, PASINI TYPE
EPIDERMOLYSIS BULLOSA LETALIS
EPIDERMOLYSIS BULLOSA SIMPLEX WITH PYLORIC ATRESIA
EPIPHYSEAL DYSPLASIA, MULTIPLE, 1; EDM1
EXOSTOSES, MULTIPLE, TYPE I
FACIOSCAPULOHUMERAL MUSCULAR DYSTROPHY 1A; FSHMD1A
FAMILIAL MEDITERRANEAN FEVER GENE; MEFV
FANCONI ANEMIA, COMPLEMENTATION GROUP C; FANCC
FANCONI ANEMIA, COMPLEMENTATION GROUP E; FANCE
FANCONI ANEMIA, COMPLEMENTATION GROUP F; FANCF
FANCONI ANEMIA, COMPLEMENTATION GROUP G
FANCONI ANEMIA, COMPLEMENTATION GROUP I; FANCI
FANCONI ANEMIA, COMPLEMENTATION GROUP J
FANCONY ANEMIA, COMPLEMENTATION GROUP A; FANCA
FRAGILE SITE MENTAL RETARDATION 1
FRAGILE SITE, FOLIC ACID TYPE, RARE, FRA(X)(q28); FRAXE
FRIEDREICH ATAXIA 1; FRDA
GANGLIOSIDOSIS, GENERALIZED GM1, TYPE I
GAUCHER DISEASE, TYPE I
GERODERMA OSTEODYSPLASTICUM; GO
GLAUCOMA 3, PRIMARY CONGENITAL, A; GLC3A
GLUCOSE-6-PHOSPHATE DEHYDROGENASE; G6PD
GLUTARIC ACIDEMIA I
GLYCOGEN STORAGE DISEASE I
GLYCOGEN STORAGE DISEASE II
GLYCOGEN STORAGE DISEASE TYPE VI
GRANULOMATOUS DISEASE, CHRONIC, X-LINKED; CGD
HEMOGLOBIN--ALPHA LOCUS 1; HBA1
HEMOGLOBIN--ALPHA LOCUS 2; HBA2
HEMOGLOBIN--BETA LOCUS; HBB
HEMOPHAGOCYTIC LYMPHOHISTIOCYTOSIS, FAMILIAL, 2
HLA MATCHING GENOTYPING
HOMOCYSTINURIA DUE TO DEFICIENCY OF N(5,10)-METHYLENETETRAHYDROFOLATE REDUCTASE ACTIVITY
HOYERAAL-HREIDARSSON SYNDROME; HHS
HUNTINGTON DISEASE; HD
HYDROCEPHALUS, X-LINKED; L1CAM
HYPERINSULINEMIC HYPOGLYCEMIA, FAMILIAL, 1; HHF1
HYPOMAGNESEMIA, RENAL, WITH OCULAR INVOLVEMENT
HYPOPHOSPHATEMIC RICKETS, X-LINKED DOMINANT
ICHTHYOSIS, LAMELLAR, 1; LI1
ICHTHYOSIS, LAMELLAR, 2; LI2
IMMUNODEFICIENCY WITH HYPER-IgM, TYPE 1; HIGM1
IMMUNODYSREGULATION, POLYENDOCRINOPATHY, AND ENTEROPATHY, X-LINKED; IPEX
INCONTINENTIA PIGMENTI; IP
ISOVALERIC ACIDEMIA; IVA
LEIGH SYNDROME; LS
LEUKOENCEPHALOPATHY WITH VANISHING WHITE MATTER; VWM
LEUKOENCEPHALOPATHY WITH VANISHING WHITE MATTER; VWM
LI-FRAUMENI SYNDROME 1; LFS1
LOEYS-DIETZ SYNDROME; LDS
LONG-CHAIN 3-HYDROXYACYL-CoA DEHYDROGENASE DEFICIENCY;HADHA
MACHADO-JOSEPH DISEASE; MJD
MARFAN SYNDROME; MFS
METAPHYSEAL CHONDRODYSPLASIA, SCHMID TYPE; MCDS
MICROCORIA-CONGENITAL NEPHROSIS SYNDROME
MICROTUBULE-ASSOCIATED PROTEIN TAU; MAPT
MIGRAINE, FAMILIAL HEMIPLEGIC, 1; FHM1
MORQUIO SYNDROME, NONKERATOSULFATE-EXCRETING TYPE
MUCOPOLYSACCHARIDOSIS TYPE II (HUNTER)
HUNTER-MCALPINE CRANIOSYNOSTOSIS SYNDROME
MUCOPOLYSACCHARIDOSIS TYPE VI
MULTIPLE ACYL-CoA DEHYDROGENASE DEFICIENCY; MADD
MULTIPLE ENDOCRINE NEOPLASIA, TYPE I; MEN1
MULTIPLE ENDOCRINE NEOPLASIA, TYPE IIA; MEN2A
MUSCULAR DYSTROPHY, BECKER TYPE; BMD
MUSCULAR DYSTROPHY, DUCHENNE TYPE; DMD
MYOPATHY, MYOFIBRILLAR, DESMIN-RELATED
MYOTUBULAR MYOPATHY 1; MTM1
N-ACETYLGLUTAMATE SYNTHASE DEFICIENCY
NEPHROSIS 1, CONGENITAL, FINNISH TYPE; NPHS1
NEUROFIBROMATOSIS, TYPE I; NF1
NEUROFIBROMATOSIS, TYPE II; NF2
NEUROPATHY, HEREDITARY SENSORY AND AUTONOMIC, TYPE I; HSAN1
NEUROPATHY, HEREDITARY SENSORY AND AUTONOMIC, TYPE III; HSAN3
NIEMANN-PICK DISEASE, TYPE A
NOONAN SYNDROME 1; NS1
NORRIE DISEASE; NDP
OCULOCUTANEOUS ALBINISM, TYPE I; OCA1
OCULOCUTANEOUS ALBINISM, TYPE II; OCA2
OPTIC ATROPHY 1; OPA1
ORNITHINE TRANSCARBAMYLASE DEFICIENCY
OSTEOGENESIS IMPERFECTA CONGENITA; OIC
OSTEOGENESIS IMPERFECTA CONGENITA; OIC
OSTEOPETROSIS, AUTOSOMAL RECESSIVE
PANCREATITIS, HEREDITARY; PCTT
PELIZAEUS-MERZBACHER-LIKE DISEASE; PMLD
PEUTZ-JEGHERS SYNDROME; PJS
POLYCYSTIC KIDNEY DISEASE 1; PKD1
POLYCYSTIC KIDNEY DISEASE 2; PKD2
POLYCYSTIC KIDNEY DISEASE, AUTOSOMAL RECESSIVE; ARPKD
POPLITEAL PTERYGIUM SYNDROME; PPS
PYRIDOXAMINE 5-PRIME-PHOSPHATE OXIDASE DEFICIENCY
RETINITIS PIGMENTOSA ;
RETINITIS PIGMENTOSA 3; RP3
RETT SYNDROME; RTT
RHESUS BLOOD GROUP, CcEe ANTIGENS; RHCE
RHESUS BLOOD GROUP, D ANTIGEN; RHD
SICKLE CELL ANEMIA
SMITH-LEMLI-OPITZ SYNDROME; SLOS
SONIC HEDGEHOG; SHH
SPINAL MUSCULAR ATROPHY, TYPE I; SMA1
SPINOCEREBELLAR ATAXIA 1; SCA1
SPINOCEREBELLAR ATAXIA 2; SCA2
SPINOCEREBELLAR ATAXIA 6; SCA6
SPINOCEREBELLAR ATAXIA 7; SCA7
STICKLER SYNDROME, TYPE I; STL1
STICKLER SYNDROME, TYPE II; STL2
SUCCINIC SEMIALDEHYDE DEHYDROGENASE DEFICIENCY
SURFACTANT METABOLISM DYSFUNCTION, PULMONARY, 3; SMDP3
SYMPHALANGISM, PROXIMAL; SYM1
TAY-SACHS DISEASE; TSD
THROMBOTIC THROMBOCYTOPENIC PURPURA, CONGENITAL; TTP
TORSION DYSTONIA 1, AUTOSOMAL DOMINANT; DYT1
TREACHER COLLINS-FRANCESCHETTI SYNDROME; TCOF
TUBEROUS SCLEROSIS TYPE 1
TUBEROUS SCLEROSIS TYPE 2
TYROSINEMIA, TYPE I
ULNAR-MAMMARY SYNDROME; UMS
VON HIPPEL-LINDAU SYNDROME; VHL
WISKOTT-ALDRICH SYNDROME; WAS
ZELLWEGER SYNDROME; ZS
ZELLWEGER SYNDROME; ZS
Ilan Tur-Kaspa MD
Founder and Medical Director, Institute for Human Reproduction (IHR), and
Director of the IVF-PGD Program, Reproductive Genetics Institute, 2825 North Halsted St. Chicago, IL 60657
Lama T. Eldahdah, MS, CGC
Reproductive Genetics Institute, 2825 North Halsted St. Chicago, IL 60657
Zeev Shoam, MD
Kaplan Medical Center, Rehovot Israel
1. Verlinsky Y, Kuliev A. Atlas of Preimplantation Genetic Diagnosis (2nd edition). Parthenon Publishing Group, London, N.Y. 2005.
2. Verlinsky Y, Kuliev A. Practical Preimplantation Genetic Diagnosis. Springer Publishing Company, new York, N.Y. 2005
3. Eldahdah L. Genetic Disorders pp.371-380, Volume 2. Diseases and Disorders. 2008. Eds Anne Hildyard and Jolyon Goddard. Marshall Cavendish: Tarrytown, New York.
4. Ao A, Shaoguang J, Rao D. First successful pregnancy outcome after preimplantation genetic diagnosis for aneuploidy screening in embryos generated from natural-cycle in vitro fertilization combined with an in vitro maturation procedure. Fertility and Sterility 2006; 85:1510.e9 –11
5. Banerjee I, Shevlin M, Taranissi M, et al. Health of children conceived after preimplantation genetic diagnosis: a preliminary outcome study. RBM Online 2008;16:
6. Cieslak-Janzen J, Tur-Kaspa I, Ilkevitch Y, Bernal A, Morris R, Verlinsky Y. Multiple micromanipulations for PGD does not affect embryo development to blastocyst. Fertil Steril 2006, 85:1826-29.
7. Colls P, Escudero T, Cekleniak N et al. Increased efficiency of preimplantation genetic diagnosis for infertility using ‘no result rescue’. Fertility and Sterility 2007
8. Coskun S, Alsmadi O. Whole genome amplification from a single cell: a new era for preimplantation genetic diagnosis. Prenat Diagn. 2007;27:297-302 (Review).
9. Coulam CB, Roussev RG, Lerner S, Zlatopolsky Z, Ilkevitch Y, Tur-Kaspa I. How to predict implantation? No correlation between embryonic aneuploidy and soluble HLA-G concentrations. Fertil Steril 2009; in press.
10. Dawson A, Griesinger G, Diedrich K. Screening oocytes by polar body biopsy. 2006; 13:104–09 (Review).
11. Donoso P, Staessen C, Fauser BC, Devroey P. Current value of preimplantation genetic aneuploidy screening in IVF. Hum Reprod Update. 2007;13:15-25 (Review).
12. Donoso P, Verpoest W, Papanikolaou EG, Liebaers I, Fatemi HM, Sermon K, Staessen C, Van der Elst J, Devroey P. Single embryo transfer in preimplantation genetic diagnosis cycles for women <36 years does not reduce delivery rate. Hum Reprod. 2007;22:1021-5.
13. Durban M, Benet J, Boada M, Fernández E, Calafell JM, Lailla JM, Sánchez-García JF, Pujol A, Egozcue J, Navarro J. PGD in female carriers of balanced Robertsonian and reciprocal translocations by first polar body analysis. Hum Reprod Update 2001;7:591-602 (Review).
14. ESHRE Ethics Task Force, Shenfield F, Pennings G, et al. Taskforce 5: preimplantation genetic diagnosis. Human Reproduction 2003; 18.3:649-51
15. Flis-Treves M, Achour-Frydman N, Kerbrat V, Munnich A, Vekemans M, Frydman R. Preimplantation genetic diagnosis and its psychological effects. J Gynecol Obstet Biol Reprod 2003;32:127-31 (French).
16. Gianaroli L, Magli M, Ferraretti A et al. The beneficial effects of preimplantation genetic diagnosis for aneuploidy support extensive clinical application. RBM Online 2005; 10.5:633–640
17. Gianaroli L, Magli MC, Ferraretti AP, Lappi M, Borghi E, Ermini B. Oocyte euploidy, pronuclear zygote morphology and embryo chromosomal complement. Human Reproduction 2007;22:241-249
18. Grace J, Toukhy T, Scriven P et al. Three hundred and thirty cycles of preimplantation genetic diagnosis for serious genetic disease: clinical considerations affecting outcome. BJOG 2006;113:1393–1401.
19. Harper JC, Pergament E, Delhanty JD. Genetics of gametes and embryos. Eur J Obstet Gynecol Reprod Biol. 2004;1:115 Suppl 1:S80-4 (Review).
20. Kahraman S, Bahçe M, Şamli H et al. Healthy births and ongoing pregnancies obtained by preimplantation genetic diagnosis in patients with advanced maternal age and recurrent implantation failure. Human Reproduction 2000; 15.9:2003-7
21. Kahraman S, Sertyel S, Findikli N et al. 2004 Effect of PGD on Implantation and ongoing pregnancy rates in cases with predominantly macrocephalic spermatozoa. Reproductive BioMedicine Online 2004(c); 9.1:79-85
22. Kuliev A, Rechitsky R, Verlinsky O, Tur Kaspa I, Kalakoutis G, Angastiniotis M, Verlinsky Y. Preimplantation diagnosis and HLA typing for haemoglobin disorders. Reproductive BioMedicine Online 2005;11:362-70.
23. Kuliev A, Rechitsky S, Laziuk K, Verlinsky O, Tur-Kaspa I, Verlinsky Y. Pre-embryonic diagnosis for Sandhoff disease. RBM Online 2006;12:328–333.
24. Kuliev A, Rechitsky S, Tur-Kaspa I, Verlinsky Y. Preimplantation genetics: Improving access to stem cell therapy. Ann N Y Acad Sci. 2005;1054:223-7 (Review).
25. Kuliev A, Verlinsky Y. Meiotic and mitotic nondisjunction: lessons from preimplantation genetic diagnosis. Hum Reprod Update 2004;10:401-7 (Review).
26. Kuliev A, Verlinsky Y. Preimplantation genetic diagnosis: technological advances to improve accuracy and range of applications. Reprod Biomed Online. 2008 16:532-8. (Review).
27. Lavery S. Preimplantation genetic diagnosis of haemophilia. Br J Haematol. 2009:144:303-7. (Review).
28. McArthur SJ, Leigh D, Marshall JT, Gee AJ, De Boer KA, Jansen RP. Blastocyst trophectoderm biopsy and preimplantation genetic diagnosis for familial onogenic disorders and chromosomal translocations. Prenat Diagn. 2008:28:434-42.
29. Montag M, van der Ven K, Rösing B, van der Ven H. Polar body biopsy: a viable alternative to preimplantation genetic diagnosis and screening. RBM Online 2009:4:6-11.
30. Munn S, Gianaroli L, Tur-Kaspa I, Magli C, Sandalinas M, Grifo J, Cram D Kahraman S, Verlinsky Y, Simpson JL. Substandard application of preimplantation genetic screening may interfere with its clinical success. Fertil Steril 2007;88:781-84.
31. Munné S, Ary J, Zouves C, et al. Wide range of chromosome abnormalities in the embryos of young egg donors. RBM Online 2006; 12.3:340-6
32. Munné S. Chromosome abnormalities and their relationship to morphology and development of human embryos. RBM Online 2006;12: 234-53 (Review).
33. Offit K, Kohut K, Clagett B, Wadsworth EA, Lafaro KJ, Cummings S, White M, Sagi M, Bernstein D, Davis JG. Cancer genetic testing and assisted reproduction. J Clin Oncol 2006;24:4775-82 (Review).
34. Otani T, Roche M, Mizuike M, Colls P, Escudero T, Munné S. Preimplantation genetic diagnosis significantly improves the pregnancy outcome of translocation carriers with a history of recurrent miscarriage and unsuccessful pregnancies. RBM Online 2006;13:869-74.
35. Pagidas K, Ying Y, Keefe D. Predictive value of preimplantation genetic diagnosis for aneuploidy screening in repeated IVF-ET cycles among women with recurrent implantation failure. J Assist Reprod Genet. 2008 25:103-6.
36. Peng W, Takabayashi H, Ikawa K. Whole genome amplification from single cells in preimplantation genetic diagnosis and prenatal diagnosis. Eur J Obstet Gynecol Reprod Biol. 2007;131:13-20 (Review).
37. Platteau P, Staessen C, Michiels A et al. Which patients with recurrent implantation failure after IVF benefit from PGD for aneuploidy screening? RBM Online 2006; 12.3:334-339
38. Popovsky M. Jewish perspectives on the use of preimplantation genetic diagnosis. J Law Med Ethics. 2007;35:699-711 (Review).
39. Rechitsky S, Kuliev A, Sharapova T, Laziuk K, Ozen S, Barsky I, Verlinsky O, Tur-Kaspa I, Verlinsky Y. Preimplantation HLA typing with aneuploidy testing. Reproductive BioMedicine Online 2006;12: 89–100.
40. Samuel GN, Strong KA, Kerridge I, Jordens CF, Ankeny RA, Shaw PJ. Establishing the role of pre-implantation genetic diagnosis with human leucocyte antigen typing: what place do "saviour siblings" have in paediatric transplantation? Arch Dis Child. 2009;94:317-20 (Review).
41. Santalo J, Grossmann M, Gimenez C, Marina F, Egozcue J, Marina S, Vidal F. The decision to cancel a preimplantation genetic diagnosis cycle. Prenat Diagn 2000;20:564-66.
42. Sermon K.D, Michiels A, Harton G et al. ESHRE PGD Consortium data collection VI: cycles from January to December 2003 with pregnancy follow-up to October 2004. Human Reproduction 2007; 22.2:323–336
43. Simpson JL, Carson SA, Cisneros P. Preimplantation genetic diagnosis (PGD) for heritable neoplasia. J Natl Cancer Inst Monogr 2005:87-90 (Review).
44. Soares, S.R, Rubio C, Rodrigo, L et al. High frequency of chromosomal abnormalities in embryos obtained from oocyte donation cycles. Fertility and Sterility 2003; 80:3
45. Strom C, Levin R, Strom S, Masciangelo C, Kuliev A, Verlinsky Y. Neonatal Outcome of Preimplantation Genetic Diagnosis by Polar Body Removal: The First 109 Infants. Pediatrics 2000;106:650-53.
46. Taranissi M, El-Toukhy T, Verlinsky Y. Influence of maternal age on the outcome of PGD for aneuploidy screening in patients with recurrent implantation failure. Reproductive BioMedicine Online 2005; 10.5:628–632
47. Tur-Kaspa I, Cieslak J, Ilkevitch N, Bernal A, Rechitsky S, Verlinsky Y. The fate of frozen/thawed embryos derived from cycles with preimplantation genetic diagnosis. Fertil Steril 2004;82: Suppl, S254-5
48. Tur-Kaspa I, Rechitsky S, Aljadeff G, Grotjan E, Verlinsky Y. Preimplantation genetic diagnosis (PGD) for all cystic fibrosis (CF) carrier couples: Strategy and cost analysis. Fertil Steril 2006;86: Suppl, S59
49. Tur-Kaspa I, Rechitsky S, Ozen RS, Sharapova T, Laziuk K, Verlinsky Y. Sperm DNA genotyping for preimplantation genetic diagnosis (PGD). Fertil Steril 2004;82: Suppl, S254.
50. Twisk M, Mastenbroek S, van Wely M, Heineman MJ, Van der Veen F, Repping S. Preimplantation genetic screening for abnormal number of chromosomes (aneuploidies) in in vitro fertilisation or intracytoplasmic sperm injection. Cochrane Database of Systematic Reviews 2006, Issue 1. Art. No.: CD005291. DOI: 10.1002/14651858.CD005291.pub2 (Review).
51. Verlinsky, Y., Ginsberg, N., Lifchez, A., Valle, J., Moise, J. and Strom, C.M. Analysis of the first polar body: preconception genetic diagnosis. Hum. Reprod 1990;7:826–29.
52. Voullaire L, Wilton L, McBain J et al. Chromosome abnormalities identified by comparative genomic hybridization in embryos from women with repeated implantation failure. Molecular Human Reproduction 2002; 8:1035–1041.
53. Weghofer A, Munné S, Brannath W, et al. The impact of LH-containing gonadotropins on diploidy rates in preimplantation embryos: long protocol stimulation. Hum Reprod 2008:23:499–503.
54. Wilton L. Preimplantation genetic diagnosis and chromosome analysis of blastomeres using comparative genomic hybridization. Hum Reprod Update. 2005;11:33-41. (Review).
55. Verlinsky Y, Rechitsky S, Schoolcraft W, Strom C, Kuliev A. Preimplantation diagnosis for Fanconi anemia combined with HLA matching. JAMA 2001;285,:3130-33.
56. Verlinsky Y Rechitsky S, Sharapova T, Laziuk K, Barsky I, Verlinsky O, Tur-Kaspa I, Kuliev A. Preimplantation diagnosis for immunodeficiencies. Reproductive BioMedicine Online 2007;14:214-223.
57. Verlinsky y, Tur-Kaspa I, Cieslak J, Bernal B, Morris R, Taranissi M, Kaplan B, Kuliev A. Preimplantation testing for chromosomal disorders improves reproductive outcome of poor prognosis patients. Reproductive BioMedicine Online 2005; 11: 219–25.