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We have analyzed single nucleotide polymorphisms (SNPs) in the XPC, XPA, and XPG genes of the nucleotide excision repair (NER) pathway in the Indian population. In the XPC gene we observed nine polymorphisms in the coding region, four polymorphisms in the intronic region, and two polymorphisms in the 5' untranslated region (UTR). In the XPA gene we observed one frequent SNP (allele frequency 0.48) within the 5' UTR at the 1665 position in a large proportion of the sample. In addition, we observed three novel heterozygous polymorphisms (a C to A transversion at position 1523 and a G to A transition at positions 1418 and 1458, with an allele frequency of 0.004) within the promoter region. In silico PCR analysis demonstrated that all three novel polymorphisms lie within a putative CpG island and that the variation at position 1418 falls within the potential GATA 1/2/3 transcription factor(s) binding site and also within the negative control element. We performed a gel retardation assay with HeLa cell nuclear extract with an oligonucleotide encompassing this region. One of the alleles found at position 1458 of the XPA gene showed a significant change in protein-DNA interaction. In the XPG gene we found five polymorphisms in the coding region and one each in the 5' UTR of exon 1 and in intron 13. KEY WORDS: NUCLEOTIDE EXCISION REPAIR, XPC, XPA, XPG, SINGLE NUCLEOTIDE POLYMORPHISM, XERODERMA PIGMENTOSUM (XP), CANCER, INDIA., The genome of any organism is under constant insult by various environmental and genetic factors. Several DNA repair mechanisms play a vital role in safeguarding the genome. Furthermore, there is [...]

The preferential occurrence of meiotic recombination at certain regions called hot spots is essential for the generation of genetic diversity and proper segregation of chromosomes during meiosis. The recombination hot spots are the sites for initiation and resolution of both crossovers and conversion events.

Research demonstrates that the rat testis associated polypyrimidine-tract binding protein (PTB) exhibits a unique structure-specific endonuclease activity different from all similar enzymes. Data indicate that the enzyme activity is related to PTB and shows two-thirds C-terminal similarity in amino acid sequence.

Research describes the DNA-condensing domain of the C-terminus of histone H1involves an octapeptide repeat motif in the C-terminus mimicking the condensing properties of histone H1 and a 34 amino acid stretch encompassing the octapeptide repeat motiff, which is directly involved in the DNA-condensation properties of histone H1.

Human homolog of bacterial MutS and S. cerevisiae MSH proteins are identified by new techniques. The homologs are known as hMSH2. Dominant mutator phenotypes are caused by the expression of hMSH2 in Escherichia coli. This indicates that hMSH2 interferes with the normal bacterial mismatch repair pathway. This behavior is similar to divergent MutS homologs. The hMSH2 maps to other human chromosomes which cause colon cancer.

Our current knowledge of recombination hot spot activity in mammalian systems implicates a role for both the primary DNA sequence and the nature of the chromatin domain around it. In mice, the only recombination hot spots mapped to date have been confined to a cluster within the major histocompatibility complex (MHC) region. We present a high resolution analysis of a new recombination hot spot in the mouse genome which maps to mouse chromosome 8 C-D. Haplotype diversity analysis across 40 different strains of mice has enabled us to map recombination breakpoints to a 1-kb interval. This hot spot has a recombination intensity that is 10to 100-fold above the genome average and has a mean gene conversion tract length of 371 bp. This meiotically active locus happens to be flanked by a transcribed region encoding a non-protein-coding RNA polymerase II transcript and the previously characterized repair site. Many of the primary DNA sequence features that have been reported for the mouse MHC hot spots are also shared by this hot spot locus and in addition, along with three other MHC hot spot loci, we show a new parallel feature of association of the crossover sites with the nuclear matrix. [ABSTRACT FROM AUTHOR]

The article discusses a study about single nucleotide polymorphisms (SNPs) in the coding regions of α-lactalbumin (LA) gene in Murrah and South Kanara breeds of buffaloes. For this study, the researchers collected blood samples from eight each of Murrah and South Kanara buffaloes. Before polymerase chain reaction (PCR) amplification, the samples have been adjusted to a concentration of 20µg/milliliter (ml). A table that shows a summary of single-nucleotide polymorphisms observed in the study is provided.

The author discusses the importance of disease biology with the increase of knowledge brought by biological researches. It states that biological researches show that diseases, which could be classified as infectious diseases and genetic disorders, have different biological functions that are result of intracellular protein-protein interactions. It argues that neuro-oncology and neurosciences will beenfit with the network biology approach of disease biology.

The article offers information on the effectiveness of Doctorate of Medicine and Philosophy (MD-PhD) or PhD-MD in addressing the translational research crisis in India. The authors mention that PhD-MD is considered as the suitable program for developing countries like India due to its deficit of medical facilities and human resources. Moreover, they said that PhD-MD can accelerate T1 translation cycle and can bridge the lack of knowledge equity in the country.