New World, but not Old World, monkeys carry several genes encoding beta-microseminoprotein

It was shown by Southern hybridization that cotton-top tamarin and common m armoset, New World monkeys, carry three or more genes encoding beta-microse minoprotein, also known as PSP94 In contrast, the genomes of Old World monk eys, as represented by rhesus macaque and sacred baboon, contain a single g ene. Clones containing three different genes encoding beta-microseminoprote in were isolated from a cotton-top tamarin genomic library. They carry two complete genes of four exons and a third gene lacking the first exon. The s tructure suggests that the three genes are functionally active and give ris e to transcripts that are approximate to 86% similar in sequence. By sequen cing one gene in full, it was shown that the introns carry an excess of int erspersed repeats, on average 29% of the introns consist of Alu repeats. A phylogenetic analysis demonstrated that the genes probably arose in New Wor ld monkeys after the separation from Old World primates.