Establishing gene Amelogenin as sex-specific marker in yak by genomic approach

Yak, an economically important bovine species considered as lifeline of the Himalaya. Indeed, this gigantic bovine is neglected because of the scientific intervention for its conservation as well as research documentation for a long time. Amelogenin is an essential protein for tooth enamel which eutherian mammals contain two copies in both X and Y chromosome each. In bovine, the deletion of a fragment of the nucleotide sequence in Y chromosome copy of exon 6 made Amelogenin an excellent sex-specific marker. Thus, an attempt was made to use the gene as an advanced molecular marker of sexing of the yak to improve breeding strategies and reproduction. The present study confirmed that the polymerase chain reaction amplification of the Amelogenin gene with a unique primer is useful in sex identification of the yak. The test is further refined with qPCR validation by quantifying the DNA copy number of the Amelogenin gene in male and female. We observed a high level of sequence polymorphisms of AMELX and AMELY in yak considered as novel identification. These tests can be further extended into several other specialized fields includingforensics, meat production and processing, and quality control.

DNA Analysis of a Microdeletion Case on Y Chromosome / 대한법의학회지

The Y-chromosome, as with other chromosomes in the cell, is subject to mutations. However, unlike autosomal genes, the Y chromosome does not undergo recombination, and therefore individuals from different geographical regions may have differing distribution patterns with respect to Y-chromosome mutations. More detailed knowledge and information regarding Y-chromosome mutations might therefore provide insights into phylogenetic history and personal identification. Here, we describe a case study involving genotype-phenotype discrepancy in an Indian male individual. We found that the mistyping in sex determination was caused by a deletion in the amelogenin Y (AMEL Y) gene. Furthermore, on examining the short tandem repeat (Y-STR) loci using the PowerPlex(R) Y23 System, we found four more deleted loci on Yp11.2 (DYS576, DYS481, DYS570, and DYS458) in this sample. We performed deletion mapping for this sample, and we propose that the microdeletion on the Yp11.2 locus occurred approximately in the 6.44 Mb to 9.75 Mb region. Previous studies have reported that the AMEL Y deletion is a common mutation in the Indian population. Taking into account regional differences, we also analyzed several area-specific Y-chromosome mutations.