Tissue-specific temporal exome capture revealed muscle-specific genes and SNPs in Indian buffalo (Bubalus bubalis)

Whole genome sequencing of buffalo is yet to be completed, and in the near future it may not be possible to identify an exome (coding region of genome) through bioinformatics for designing probes to capture it. In the present study, we employed in solution hybridization to sequence tissue specific temporal exomes (TST exome) in buffalo. We utilized cDNA prepared from buffalo muscle tissue as a probe to capture TST exomes from the buffalo genome. This resulted in a prominent reduction of repeat sequences (up to 40%) and an enrichment of coding sequences (up to 60%). Enriched targets were sequenced on a 454 pyro-sequencing platform, generating 101,244 reads containing 24,127,779 high quality bases. The data revealed 40,100 variations, of which 403 were indels and 39,218 SNPs containing 195 nonsynonymous candidate SNPs in protein-coding regions. The study has indicated that 80% of the total genes identified from capture data were expressed in muscle tissue. The present study is the first of its kind to sequence TST exomes captured by use of cDNA molecules for SNPs found in the coding region without any prior sequence information of targeted molecules.