Book Review

Fecundity in human is much lower than in other mammals. The reason is high frequency of errors in gametogenesis, leading to an abnormality in embryos and thus wastage, either before, during or after implantation. The causes are mostly chromosomal and genetic. The main application of genetics is to predict and prevent a disorder, thus decreasing its burden right from the planning of reproduction. The ideal time should be from the time of pre-conception so that prediction and prevention (primary and/or secondary) is possible. To apply for its role in humans, a new branch of medicine has appeared as Human Reproductive Genetics, that deals with genetics of the human reproductive process, both natural and assisted reproduction.

This book edited by Juan A. Garcia-Velasco and Emre Seli, provides updated information on various aspects of human reproductive genetics, including its application. The book has four sections (A-D) and 18 chapters (1-18) contributed by well-known experts in the field of infertility, reproductive endocrinology, genetics, obstetrics and gynaecology, assisted reproductive technology (ART), etc. mostly from the European countries (Spain, UK, Belgium, Denmark, the Netherlands, etc.) and the United States.

The book begins with the preface that summarizes every section of the book including recent genetic advances and developments that lead to improvements in patient care. The first section (A) of the book has five chapters (1-5) that summarize basic genetics, cytogenetics, genetic causes of gynaecologic diseases, molecular biology techniques and epigenetics. New developments in molecular biology such as next-generation sequencing and microarray are explained, so the readers can understand what these technologies can do for patients along with their limitations. The second section (B) of the book has eight chapters (6-13) that focus on the relationship between genetics and reproductive disorders causing male and female infertility (endometriosis, PCOS, POI, mitochondrial diseases, etc.). The endometrial receptivity, pre-natal and carrier screening approaches are also covered. The third section (C) of the book has two chapters (14 and 15) that describe the latest genetic tests for a pre-implantation embryo with (invasive) and without (non-invasive) embryo biopsy. The last (fourth) section (D) of the book has three chapters (16-18) that address reproductive genetic counselling including psychological aspects and bioethics.

Advances in molecular (next-generation sequencing, microarray and gene editing) and reproductive (gamete/polar body/embryo biopsy, in vitro gametogenesis, cryopreservation/vitrification, cloning, etc.) technologies with the introduction of pre-implantation genetic testing (PGT) for aneuploidy screening, structural rearrangement, monogenic disorder, polygenic disorder (PGT-P) or even genomic profiling (PGP) and non-invasive PGT, etc.; non-invasive pre-natal screening/testing (NIPS/NIPT) for common chromosomal abnormalities (chromosome 21, 18, 13, X and Y), rapid pre-natal diagnosis (PND) for chromosomal, copy number, monogenic disorders, etc. and improved foetal imaging (foetal ultrasonography/foetal real-time MRI) have increased this drive and expectations. The NIPT/NIPS (from cell-free foetal DNA in maternal blood) and NIPD/non-invasive PND (from isolated foetal cells in maternal blood) are evolving technologies for screening/diagnosis of foetal chromosomal and copy number abnormalities from maternal blood. The low false-positive and false-negative rates of NIPT and diagnostic accuracy of NIPD will allow women to avoid the otherwise invasive procedures of PND in the coming years.

Infertility is a major area in human reproductive genetics. Genetics accounts for 15-30 per cent of male and 10-15 per cent of female infertility. Genetics and epigenetics are becoming more important following the advent of in vitro fertilization and intracytoplasmic sperm injection (ICSI) as these procedures lead to more genetic abnormality in offspring since it bypasses natural protective mechanisms.

Advances in reproductive technology such as cellular reprogramming or cellular differentiation/dedifferentiation and gene editing have created another dimension for reproductive genetics. Now, in the laboratory, stem cells can be manipulated to become specialized cells and in the future, could be used to treat infertility. Embryonic stem cells can be differentiated into gametes (sperm/oocytes) to treat infertility or into trophoblast for studying human placental development and function. Recent progress in germline stem cell isolation and culture may provide a platform for in vitro gamete development and may begin a new era of gametogenesis in a dish and personalized infertility treatment in the coming years.

On the whole, this book is informative and covers cutting-edge areas of reproductive genetics in a brief, but effective manner, although some of the areas have been left untouched and we hope the next edition will cover those topics. This book has brought together well-renowned experts in the field across Europe and the USA, and their contributions will help in better understanding the subject. The book is written well, concise, informative and will provide information to readers for a better understanding of human reproductive genetics.

Rapid dissemination of information has affected daily reproductive care so much that an understanding of human reproductive genetics is essential for all reproductive specialists, in particular, to know the risks of a genetic disorder and how to prevent it. This knowledge will protect reproductive specialists from medico-legal consequences following failure in preventing genetic disorders in infertile couples requiring ART.