Article in Journal ()
Harvey SC, Boonphakdee C, Campos-Ramos R, Ezaz MT, Griffin DK, Bromage NR & Penman D (2003) Analysis of repetitive DNA sequences in the sex chromosomes of Oreochromis niloticus, Cytogenetic and Genome Research, 101 (3-4), pp. 314-319.
In the Nile tilapia, Oreochromis niloticus, sex determination is primarily genetic, with XX females and XY males. While the X and Y chromosomes (the largest pair) cannot be distinguished in mitotic chromosome spreads, analysis of comparative hybridization of X and Y chromosome derived probes (produced, by microdissection and DOP-PCR, from XX and YY genotypes, respectively) to different genotypes (XX, XY and YY) has demonstrated that sequence differences exist between the sex chromosomes. Here we report the characterization of these probes, showing that a significant proportion of the amplified sequences represent various transposable elements. We further demonstrate that concentrations of a number of these individual elements are found on the sex chromosomes and that the distribution of two such elements differs between the X and Y chromosomes. These findings are discussed in relation to sex chromosome differentiation in O. niloticus and to the changes expected during the early stages of sex chromosome evolution.
|Authors||Harvey Simon C, Boonphakdee Chuta, Campos-Ramos Rafael, Ezaz M Tariq, Griffin Darren K, Bromage Niall R, Penman David|
Cytogenetic and Genome Research: Volume 101, Issue 3-4 (2003)