Isolation and Characterization of y-Linked Genes Regulating Male Fertility in Alpacas

Isolation and Characterization of y-Linked Genes Regulating Male Fertility in Alpacas

Principal investigator:

Terje Raudsepp, PhD
Texas A&M University

Current knowledge about the genetics of male reproduction and fertility in alpacas is limited hindering distinction between conditions caused by genes, from those affected by management. Furthermore, alpaca reference genome is from a female and does not contain sequences from the Y chromosome — the chromosome that is known to be enriched with spermatogenesis and male reproduction genes in humans, mice and several domestic species (horse, pig, cattle, cat, dog). Here we initiated research on the alpaca Y chromosome. The chromosome is present only in males and is exclusively inherited through patrilines. We isolated and characterized, for the first time, Y chromosome genes in alpacas and evaluated their expression in testis and estimated their approximate copy numbers. We identified 87 putative alpaca Y chromosome genes, confirmed male specificity of 12 genes and showed that the gene encoding for testis specific protein in Y (TSPY) has multiple copies in the alpaca Y chromosome. The study initiated Y chromosome research in alpacas and camelids in general. In long-term perspective, the finding will have applications in genetic evaluation of male fertility and for the study of the history of paternal lineages of populations and breeds in all South American camelids.