Finding of hybridization effect for chromosome alterations in night monkeys.

Night monkey hybrids exhibit de novo genomic and karyotypic alterations: the first such case in primates

Hirohisa Hirai, Yuriko Hirai, Mayumi Morimoto, Akihisa Kneko, Yoshiro Kamanaka, Akihiko Koga

Abstract

Using molecular chromosomal analyses, we discovered night monkey hybrids produced in captivity from matings between a female Aotus azarae boliviensis (2n = 50) and a male A. lemurinus griseimembra (2n = 53). The parents produced seven offspring in total, including one male and six females ăŕ a pattern consistent with HaldaneăŕŃÔ rule. Chromosomal studies were conducted on four of the hybrid offspring. Two of them showed relatively ăŕĎÔimpleăŕ mixture karyotypes, including different chromosome numbers (2n = 51, 52), which were formed because of a heteromorphic autosome pair in the father (n = 26, 27). The other two hybrid monkeys exhibited de novo genomic and karyotypic alterations. Detailed analysis of the alterations revealed that one individual carried a mixture karyotype of the two parental species and an X chromosome trisomy (53, XXX). The second individual displayed trisomy of chromosome 18 (52,XX,+18) and a reciprocal translocation between autosomes 21 and 23 (52,XX,+18,t(21;23)). Interestingly, the second monkey exhibited mosaicism among blood cells (mos52,XX,+18[87]/52,XX,+18,t(21;23)[85]) but only a single karyotype (52,XX,+18) in skin fibroblast cells. Such occurrence of trisomies in hybrid individuals is a unique finding in placental mammals.

Bibliographic information

Genome Biology and Evolution (22 March 2017)
DOI: https://doi.org/10.1093/gbe/evx058

2017/04/10 Primate Research Institute