Gary Harton

• PhD
• Illumina

Chromosome testing strategies, such as PGT-A, are designed to improve an IVF embryo transfer outcome by avoiding the unwitting selection of aneuploid embryos as occurs in morphology-based approaches. Newer testing technologies have revealed that some embryos may appear to have intermediate whole chromosome (or parts of a chromosome termed segmental...

Cystic fibrosis (CF) is one of the most common indications for preimplantation genetic diagnosis (PGD) for single gene disorders, giving couples the opportunity to conceive unaffected children without having to consider termination of pregnancy. However, there are no available standardized protocols, so that each center has to develop its own diagn...

IntroductionPreimplantation genetic diagnosis (PGD) of single gene defects by genetic analysis of single or small numbers of cells biopsied from in vitro fertilization (IVF) embryos is clinically well-established. Targeted haplotyping by multiplex fluorescent polymerase chain reaction (PCR) of closely linked or intragenic short tandem repeat (STR)...

Preimplantation genetic diagnosis (PGD) for monogenic disorders currently involves polymerase chain reaction (PCR)-based methods, which must be robust, sensitive and highly accurate, precluding misdiagnosis. Twelve adverse misdiagnoses reported to the ESHRE PGD-Consortium are likely an underestimate. This retrospective study, involving six PGD cent...

Objective To assess the relationship between maternal age, chromosome abnormality, implantation, and pregnancy loss. Design Multicenter retrospective study. Setting IVF centers in the United States. Patient(s) IVF patients undergoing chromosome screening. Intervention(s) Embryo biopsy on day 3 or day 5/6 with preimplantation genetic diagnosis (...

Study question: How has the interface between genetics and assisted reproduction technology (ART) evolved since 2005? Summary answer: The interface between ART and genetics has become more entwined as we increase our understanding about the genetics of infertility and we are able to perform more comprehensive genetic testing. What is known alre...

Study question Is blastulation rate associated with euploid embryo status? Summary answer Euploid embryos appear to be three times more likely to undergo blastulation than aneuploid embryos among six to eight cell embryos undergoing blastomere biopsy and array CGH for Pregestational Genetic Screening (PGS). What is known already Recent studies on...

Preimplantation genetic diagnosis (PGD) was first performed over 20 years ago and has become an accepted part of genetic testing and assisted reproduction worldwide. The techniques and protocols necessary to carry out genetic testing at the single-cell level can be difficult to master and have been developed independently by the laboratories worldw...

Introduction Although ICSI can remedy many types of male infertility, some conditions remain challenging. Injection of immotile spermatozoa has a strong negative effect on fertilization and pregnancy rates. Therefore, different methods are applied in order to differentiate viable and non-viable immotile spermatozoa for ICSI. Laser-assisted immotile...

Introduction The ESHRE PGD Consortium was set up in 1997 and since then has been actively collecting data on PGD and PGS. The PGD Consortium currently has four Working Groups to look at important aspects of PGD: data collection and database, accreditation, misdiagnosis monitoring and audit, and sharing of molecular methods. In 2010 the guidelines g...

The 11th report of the European Society of Human Reproduction and Embryology Preimplantation Genetic Diagnosis Consortium is presented, documenting cycles collected for the calendar year 2008 and follow-up of the pregnancies and babies born until October 2009 which resulted from these cycles. Since the beginning of the data collections, there has b...

Since it was established in 1997, the ESHRE PGD Consortium has been collecting data from international preimplantation genetic diagnosis (PGD) centres. Ten papers have been published, including data from January 1997 to December 2007. The data collection originally used a hard-copy format, then an excel database and finally a FileMaker Pro database...

Infertility in humans is surprisingly common occurring in approximately 15% of the population wishing to start a family. Despite this, the molecular and genetic factors underlying the cause of infertility remain largely undiscovered. Nevertheless, more and more genetic factors associated with infertility are being identified. This review will focus...

Introduction The ESHRE PGD Consortium was set up in 1997 and since then has been actively collecting data on PGD and PGS. The PGD Consortium currently has five Working Groups to look at important aspects of PGD: data collection and database, accreditation, misdiagnosis monitoring and audit, and sharing of molecular methods and the newly formed work...

Diagnosis of embryos for chromosome abnormalities, i.e. aneuploidy screening, has been invigorated by the introduction of microarray-based testing methods allowing analysis of 24 chromosomes in one test. Recent data have been suggestive of increased implantation and pregnancy rates following microarray testing. Preimplantation genetic diagnosis for...

Introduction: Blastocyst culture and transfer increases implantation rates and supports eSET but has been associated with increases in imprinting disorders and monozygotic twins (MZT) – the latter having far worse clinical outcomes than dizygotic twins. We investigated MZT rates following BT or cleavage stage (CT) embryo transfer by retrospective r...

Introduction: PGD for translocations using FISH has been successful in reducing the risk of miscarriage in carrier couples to about 10%. However, for older translocation carriers with elevated risk of producing both aneuploid and unbalanced embryos, microarrays may be more advantageous. One objective of this study was to validate array comparative...

The 10th report of the European Society of Human Reproduction and Embryology (ESHRE) PGD Consortium is presented, documenting cycles collected for the calendar year 2007 and follow-up of the pregnancies and babies born until October 2008 which resulted from these cycles. Since the beginning of the data collections there has been a steady increase i...

In 2005, the European Society for Human Reproduction and Embryology (ESHRE) Preimplantation Genetic Diagnosis (PGD) Consortium published a set of Guidelines for Best Practice to give information, support and guidance to potential, existing and fledgling PGD programmes (Thornhill AR, De Die-Smulders CE, Geraedts JP, Harper JC, Harton GL, Lavery SA,...

In 2005, the European Society for Human Reproduction and Embryology (ESHRE) PGD Consortium published a set of Guidelines for Best Practice PGD to give information, support and guidance to potential, existing and fledgling PGD programmes. Subsequent years have seen the introduction of new technologies as well as the evolution of current techniques....

In 2005, the European Society for Human Reproduction and Embryology (ESHRE) PGD Consortium published a set of Guidelines for Best Practice PGD to give information, support and guidance to potential, existing and fledgling PGD programmes. The subsequent years have seen the introduction of new technologies as well as evolution of current techniques....

In 2005, the European Society for Human Reproduction and Embryology (ESHRE) PGD Consortium published a set of Guidelines for Best Practice PGD to give information, support and guidance to potential, existing and fledgling PGD programmes. The subsequent years have seen the introduction of a number of new technologies as well as the evolution of curr...

In preimplantation genetic diagnosis (PGD), polymerase chain reaction has been used to detect monogenic disorders, and in PGD/preimplantation genetic screening (PGS), fluorescence in situ hybridization (FISH) has been used to analyze chromosomes. Ten randomized controlled trials (RCTs) using FISH-based PGS on cleavage-stage embryos and one on blast...

Introduction: The ESHRE PGD Consortium was set up in 1997 and has been actively collecting data on PGD and PGS since then. The PGD Consortium has set up five working groups to look at important aspects of PGD; data collection and database, accreditation, misdiagnosis monitoring and audit, best practice guidelines and sharing of molecular methods....

Since 2004, there have been 11 randomized controlled trials (RCTs) mainly for advanced maternal age (AMA), which have shown no benefit of performing preimplantation genetic screening (PGS). Ten of the RCTs have been performed at the cleavage stage and one at the blastocyst stage. It is probable that the high levels of chromosomal mosaicism at cleav...

To develop and assess a polymerase chain reaction (PCR)-based preimplantation genetic diagnosis (PGD) approach for detection of chromosomal imbalances in embryos. A prospective study of embryos derived from chromosome translocation carriers that have undergone PGD using a novel molecular-based approach. A reference molecular genetics laboratory spe...

The use of genome wide single nucleotide polymorphism (SNP) arrays for high resolution molecular cytogenetic analysis using a combination of quantitative and genotype analysis is well established. This study demonstrates that by Mendelian analysis of the SNP genotypes of the parents and a sibling or other appropriate family member to establish phas...

The ninth report of the European Society of Human Reproduction and Embryology Preimplantation Genetic Diagnosis Consortium is presented documenting cycles collected for the calendar year 2006 and follow-up of the pregnancies and babies born until October 2007, which resulted from these cycles. Since the beginning of the data collections there has b...

The eighth report of the European Society of Human Reproduction and Embryology PGD Consortium is presented documenting cycles collected for the calendar year 2005 and follow-up of the pregnancies and babies born until October 2006 which resulted from these cycles. For the first time, the delivery rates for each indication are presented and also the...

The seventh report of the ESHRE PGD Consortium is presented documenting cycles collected for the calendar year 2004 and follow-up of the pregnancies and babies born subsequent to these cycles up to October 2005. Since the beginning of the data collections, there has been a steady increase in the number of cycles, pregnancies and babies reported. Fo...

Preimplantation genetic diagnosis for aneuploidy screening (preimplantation genetic screening—PGS) has been used to detect chromosomally normal embryos from subfertile patients. The main indications are advanced maternal age (AMA), repeated implantation failure, repeated miscarriages and severe male factor infertility. Many non-randomized PGS studi...

The sixth report of the ESHRE PGD Consortium is presented, relating to cycles collected for the calendar year 2003 and follow-up of the pregnancies and babies born up to October 2004. Since the beginning of the data collections, there has been a steady rise in the number of cycles, pregnancies and babies reported. For this report, 50 centres partic...

The fifth report of the ESHRE PGD Consortium is presented (data collection V). For the first time, the cycle data were collected for one calendar year (2002) in the following October, so that data collection was complete for pregnancies and babies. The data were collected using a Filemaker Pro database and divided into referrals, cycles, pregnancie...

Among the many educational materials produced by the European Society of Human Reproduction and Embryology (ESHRE) are guidelines. ESHRE guidelines may be developed for many reasons but their intent is always to promote best quality practices in reproductive medicine. In an era in which preimplantation genetic diagnosis (PGD) has become a reality,...

Individuals at risk for Huntington disease face difficult decisions regarding their reproductive options. Most do not wish to pass on the gene for Huntington disease to their children, but may not be prepared themselves to undergo presymptomatic testing and learn their genetic status. For these reasons, many at-risk individuals with a family histor...

Marfan syndrome is an autosomal dominant disorder affecting the skeletal, ocular, and cardiovascular systems. Defects in the gene that encodes fibrillin-1 (FBN1), the main structural component of the elastin-associated microfibrils, are responsible for the disorder. Molecular diagnosis in families with Marfan syndrome can be undertaken by using int...

Couples with children who have spinal muscular atrophy type I (SMA) face a 25% risk of having affected offspring with spontaneous conception. Preimplantation genetic testing (PGT) is possible for the deletions in the survival motor neuron (SMN) gene that have been identified in 98% of SMA type I cases. PGT would provide new reproductive options for...

The in vitro fertilization technology coupled with the ability to amplify DNA from a single cell has been used for the preimplantation genetic diagnosis of Marfan syndrome. An intragenic FBN1 gene marker has been used to track the inheritance of this disorder in a family. Marker genotyping was established following two rounds of amplification. When...

Marfan syndrome (MFS) is an autosomal dominant disease that affects the skeletal, ocular and cardiovascular systems. Defects in the gene that codes for fibrillin (FBN-1) are responsible for MFS. Here we report the world‘s first use of preimplantation genetic testing (PGT) to achieve a clinical pregnancy and live birth of a baby free of a Marfan mut...

The discovery of nucleated erythrocytes in maternal circulation provides a potential source for non-invasive prenatal diagnosis. We have evaluated the use of a three-stage procedure to determine the number of cells that are of fetal rather than maternal origin. First, monoclonal antibodies specific for CD45 and CD14 were used in conjunction with a...

The discovery of nucleated erythrocytes in maternal circulation provides a potential source for non-invasive prenatal diagnosis. We have evaluated the use of a three-stage procedure to determine the number of cells that are of fetal rather than maternal origin. First, monoclonal antibodies specific for CD45 and CD14 were used in conjunction with a...

We report the world's first clinical pregnancy resulting from DNA-based enrichment for X-bearing human spermatozoa, for prevention of X-linked hydrocephalus. Sperm separation was followed by embryo biopsy and nested multiplex polymerase chain reaction (PCR) for gender determination. Enriched populations of X-bearing spermatozoa ranging from 80 to 8...

We have developed an improved method for polymerase chain reaction (PCR)-based sizing of the CCG repeat region at the fragile X locus, FMR-1. This method is designed to optimize denaturation and replication of long repeats with high G + C content, which are otherwise refractory to amplification. The method utilizes nested PCR primers to increase se...

Dependable methods were developed for preimplantation sexing of human IVF embryos, for use in clinical settings where prospective parents are at high risk for transmission of X-linked diseases. Using single cultured cells and blastomeres from human embryos as model systems, a multiplex protocol was developed for rapid analysis via nested polymerase...