Chromosome sorting of primates: Isolation and identification of Y chromosome in green monkeys

Abstract

ABSTRACT. Single laser flow cytometry was applied to the karyotype analysis of green monkeys. Clear sex difference in flow karyotype was recognized in this monkey, because Y chromosome could be identified as a single peak in the histogram of male specimens. We could isolate Y chromosome of this species by the use of a cell sorter, and demonstrate by polymerase chain reaction that the sorted-out chromosomes contained the Y chromosome specific nucleotide sequence (SRY). This chromosome sorting technique provides a powerful strategy for constructing the DNA library specific to Y chromosome in this species.

Maternal or fetal origin of rhesus monkey (Macaca mulatta) amniotic fluid leukocytes can be identified by polymerase chain reaction using the zinc finger Y gene

“…Starting with human DYZ-1 and ZFY primers, we hybridized rhesus DNA under low stringency, isolated PCR products, and sequenced the products to develop our own rhesus-specific DYZ-1 and ZFY gene probes. The PCR product using DYZ-1 primers gave false-positive results when using female rhesus monkey peripheral blood cells, as has been reported in other nonhuman and human primates [Handyside et al, 1989;Lo et al, 1989;Nakagome et al, 1990;Björkqvist et al, 1994;Murayama et al, 1995]. DYZ-1 is also a poor locus for quantification, as the number of repeats within chromosomes of individuals varies from 800-5,000 copies [Nakahori et al, 1991].…”

“…Thus, it is not surprising that many of the sequences are similar in both chromosomes as a relic of the ancestral pair, which increases the difficulty of selecting specific loci for molecular sex identification. Although DYZ-1 locus has been useful for sex identification in human and several other primates [Murayama et al, 1995], we found it unsuitable in the rhesus monkey. The rapid evolution of the SRY locus between species [Savatier et al, 1987;Tucker & Lundrigan, 1993;Whitfield et al, 1993] contrasts with the constancy of the ZFY exons reported across mammalian species [Page et al, 1987].…”

“…The second target commonly used for Y chromosome identification is the DYZ-1 locus, containing highly repetitive sequences. This repetition of sequence minimizes the sample size or the number of cycles needed to sufficiently amplify the sequence via PCR, but may contribute to a high false-positive rate [Handyside et al, 1989;Lo et al, 1989;Nakagome et al, 1990;Björkqvist et al, 1994;Murayama et al, 1995].…”