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Preimplantation genetic testing (PGT) for monogenic disorders and assisted reproductive technology have evolved and progressed in tandem. PGT started with single-cell polymerase chain reaction (PCR) followed by fluorescent in situ hybridisation for a limited number of chromosomes, later called 'preimplantation genetic diagnosis (PGD) version 1'. This review highlights the various molecular genetic techniques that have evolved to detect specific inherited monogenic disorders in the preimplantation embryo. Literature review in English was performed in PubMed from 1990 to 2021, using the term 'preimplantation genetic diagnosis'. With whole-genome amplification, multiple copies of embryonic DNA were created. This helped in avoiding misdiagnosis caused by allele dropout. Multiplex fluorescent PCR analysed informative short tandem repeats (STR) and detected mutations simultaneously on automated capillary electrophoresis sequencers by mini-sequencing. Comparative genomic hybridisation (CGH) and array CGH were used for 24 chromosome aneuploidy screening. Subsequently, aneuploidies were detected by next-generation sequencing using single-nucleotide polymorphism arrays, while STR markers were used for haplotyping. 'PGD version 2' included accurate marker-based diagnosis of most monogenic disorders and detection of aneuploidy of all chromosomes. Human leukocyte antigen matching of embryos has important implications in diagnosis and cure of haemoglobinopathies and immunodeficiencies in children by means of matched related haematopoietic stem cell transplantation from an unaffected 'saviour sibling' obtained by PGT. [ABSTRACT FROM AUTHOR]

Background: Antimullerian hormone (AMH) is a key marker of ovarian reserve and predictor of response to fertility treatment. Aim: To understand the prevalence of low ovarian reserve in Indian women seeking infertility treatment, compare their AMH with age-matched fertile Indian controls and understand ethnic differences with Caucasian women. Setting and Design: Retrospective observational study done as collaboration between our in vitro fertilization centre and a laboratory with Pan-India presence. Materials and Methods: Women aged 20–44 years were selected as Group A (seeking infertility treatment n = 54,473), Group B (conceived naturally in the past; n = 283) and Group C (data of Caucasian women; n = 718). Serum AMH levels were measured and descriptive analysis done. Statistical Analysis: Descriptive statistics and Chi-square test. Results: In Group A, 28.7%, 48.7% and 70.6% of women aged <30 years, 30–34 years and 35–39 years had serum AMH levels ≤2 ng/mL and the proportions were higher than Group B. The rate at which median AMH decreased was 1.1–2 times faster in Group B as compared to Group C. The decrease in median AMH across age groups in Group A was similar to Group B. Conclusions: Indian women in their late twenties and early thirties visiting fertility centers showed a worrisome trend of low AMH. Our study can be used as a reference for those women considering postponing pregnancy. It may be time to look at intangible cultural factors linked to social habits, ethnicity, diet, genetic predispositions, and environmental factors like endocrine disrupting chemicals contributing to premature ovarian senescence. [ABSTRACT FROM AUTHOR]

Neonatal-Onset Multisystem Inflammatory Disease (NOMID) or Chronic Infantile Neurologic Cutaneous Articular (CINCA) syndrome is a monogenic autoinflammatory disorder characterized by urticarial skin rash, fever, chronic meningitis and joint manifestations. Here we report a case of an Indian male child who presented at the age of 9 months with fever, respiratory distress, urticarial skin rash, arthritis, and neuroregression. Suspecting NOMID/CINCA syndrome, the child's blood was sent to the Jaslok Hospital and Research Centre for mutation analysis of the CIAS1/NLRP3 gene. The DNA was screened for mutations in exon 3 of CIAS1/NLRP3 gene by automated Sanger sequencing. DNA sequencing showed a novel heterozygous c.1813A➔G, p.R605G mutation in exon 3 of CIAS1/NLRP3 gene (ref no NM_001243133.1). His parents tested negative for this mutation. We therefore identified a novel de novo mutation in this family in the CIAS1/NLRP3 gene responsible for the child's clinical features. [ABSTRACT FROM AUTHOR]

We here report a case of a 23-year-old female from Mumbai, Maharashtra, India who was detected to carry the α chain variant Hb J-Norfolk [HBA2: c.173G>A (or HBA1]. She had no clinical symptoms and was referred to us for routine investigations and screening. An abnormal peak was detected on both high performance liquid chromatography (HPLC) and capillary electrophoresis (CE) with a fast-moving band on cellulose acetate electrophoresis. There is no detailed study on the HPLC and CE pattern of this hemoglobin (Hb) variant, and therefore, this study will help in detecting and avoiding missing these variants during routine investigations and population screening. This is the first report of this variant in the Indian population. [ABSTRACT FROM AUTHOR]

Preimplantation genetic testing (PGT) is an early form of prenatal genetic diagnosis where abnormal embryos are identified, thereby allowing transfer of genetically normal embryos. This technology has become an integral part of Assisted Reproductive Technology (ART) procedures. Initial experiments with animals as early as 1890 and those in the mid and later part of the last century paved the forward path of ART and PGT. This review article covers the evolution of PGT and is a pointer toward current and fast-evolving technology, allowing scientists and doctors to better comprehend human reproduction, and ensure healthy pregnancy outcomes., Competing Interests: There are no conflicts of interest.