Chromosomal Abnormalities in Embryos

From patients with a poor prognosis of pregnancy, 1620 embryos generated in vitro and chromosomal analysis was performed on these embryos. The result was yielded in 1596 embryos, out of them 536(34%) were euploid and 1060(66%) carried chromosomal abnormalities. In addition, 92% of embryos with multinucleated cells were diagnosed mosaics whereas the 86% of chromosomal abnormalities were associated to the presence of cytoplasmic concentration. For the derivation of the normal embryonic stem cell (ESC)lines and developmental modelling aneuploid embryos have been used. Genetic diagnosis at the cleavage or blastocyst stage could be partly abnormal because during the preimplantation diploid- aneuploid mosaic embryos was most frequently observed. From a single cell of a particular embryo the chromosomal status of that embryo can be determined, thus the prevalence of mosaicism. Detection of aneuploidy in single cells have been developed recently. After conducting research methods, it was confirmed that aneuploidy is a common feature of human oocytes and preimplantation embryos. The detection of segmental aneuploidy is currently considered problematic for embryo diagnosis and patient counselling, so the data are of great relevance for preimplantation genetic testing. The first major milestone in early mammalian embryogenesis was the formation of a totipotence blastocyst which is capable of implantation. The whole chromosomal abnormalities, or aneuploidy, determines whether the human embryos will arrest or reach the blastocyst stage. Certain embryos can still form blastocyst depending on the type of chromosomal abnormalities and that can be morphologically indistinguishable from chromosomally normal embryos.

Human leukocyte antigen alleles, genotypes and haplotypes frequencies in renal transplant donors and recipients from West Central India.

BACKGROUND: Human leukocyte antigen (HLA) is comprised of a highly polymorphic set of genes which determines the histocompatibility of organ transplantation. The present study was undertaken to identify HLA class I and class II allele, genotype and haplotype frequencies in renal transplant recipients and donors from West Central India. MATERIALS AND METHODS: HLA typing was carried out using Polymerase Chain Reaction-Sequence Specific Primer in 552 live related and unrelated renal transplant recipients and donors. RESULTS: The most frequent HLA class I and class II alleles and their frequencies in recipients were HLA-AFNx0101 (0.1685) and AFNx0102 (0.1649), HLA-BFNx0135 (0.1322), and HLA-DR beta 1 (DRB 1)FNx0115 (0.2192), whereas in donors, these were HLA-AFNx0102 (0.1848) and AFNx0101 (0.1667), HLA-BFNx0135 (0.1359), and HLA-DRB1FNx0115 (0.2409). The two-locus haplotype statistical analysis revealed HLA-AFNx0102-B61 as the most common haplotype with the frequency of 0.0487 and 0.0510 in recipients and donors, respectively. Further, among the three locus haplotypes HLA-AFNx0133-BFNx0144-DRB1FNx0107 and HLA-AFNx0102-BFNx0161-DRB1FNx0115 were the most common haplotypes with frequencies 0.0362 and 0.0326, respectively in recipients and 0.0236 and 0.0323, respectively in donors. Genotype frequency revealed a high prevalence of genotype HLA-AFNx0102/AFNx0124 in recipients (0.058) compared to donors (0.0109) whereas low prevalence of HLA-AFNx0101/AFNx0102 in recipients (0.0435) than in donors (0.0797). The phylogenetic and principal component analysis of HLA allele and haplotype frequency distribution revealed genetic similarities of various ethnic groups. Further, case control analysis provides preliminary evidence of association of HLA-A genotype (P < 0.05) with renal failure. CONCLUSION: This study will be helpful in suitable donor search besides providing valuable information for population genetics and HLA disease association analysis.

Corpora amylacea deposition in the hippocampus of patients with mesial temporal lobe epilepsy: A new role for an old gene.

BACKGROUND: Mesial temporal lobe epilepsy (MTLE) is the most common medically refractory epilepsy syndrome in adults, and hippocampal sclerosis (HS) is the most frequently encountered lesion in patients with MTLE. Premature accumulation of corpora amylacea (CoA), which plays an important role in the sequestration of toxic cellular metabolites, is found in the hippocampus of 50–60% of the patients who undergo surgery for medically refractory MTLE-HS. However, the etiopathogenesis and clinical importance of this phenomenon are still uncertain. The ABCB1 gene product P-glycoprotein (P-gp) plays a prominent role as an antiapoptotic factor in addition to its efflux transporter function. ABCB1 polymorphism has been found to be associated with downregulation of P-gp expression. We hypothesized that a similar polymorphism will be found in patients with CoA deposition, as the polymorphism predisposes the hippocampal neuronal and glial cells to seizure-induced excitotoxic damage and CoA formation ensues as a buffer response. MATERIALS AND METHODS: We compared five single nucleotide polymorphisms in the ABCB1 gene Ex06+139C/T (rs1202168), Ex 12 C1236T (rs1128503), Ex 17-76T/A (rs1922242), Ex 21 G2677T/A (rs2032582), Ex26 C3435T (rs1045642) among 46 MTLE-HS patients of south Indian ancestry with and without CoA accumulation. RESULTS: We found that subjects carrying the Ex-76T/A polymorphism (TA genotype) had a five-times higher risk of developing CoA accumulation than subjects without this genotype (Odds ratio 5.0, 95% confidence intervals 1.34-18.55; P = 0.016). CONCLUSION: We speculate that rs1922242 polymorphism results in the downregulation of P-gp function, which predisposes the hippocampal cells to seizure-induced apoptosis, and CoA gets accumulated as a buffer response.

Universal protocol for generating 100bp size standard for endless usage

Developing countries are facing severe bottlenecks in the technological advancement in biotechnology, due to restrictions imposed by patent protected products and protocols. This calls for designing of simple and cost-effective alternatives for the indispensable products like DNA molecular weight markers. We demonstrate a novel, rapid and cost-effective method of making in-house 100bp ladder for routine use. In our method we use a single forward primer and five reverse primers designed on the backbone sequence of a commonly used vector template. These primers are used at a universal annealing temperature to amplify ten DNA fragments of accurate size ranging from 100bp to 1000bp. Our PCR-based method can provide size standards for an endless usage.