Sex chromosome "dosage compensation" systems occur in animals as diverse as mammals, insects and nematodes to equalise expression of sex-linked genes. We have recently shown, for the first time, that dosage compensation occurs for chicken sex chromosomes.
Female Birds are heterogametic (ZW) while males are homogametic(ZZ). Using real-time quantitaive PCR, we have demonstrated equivalent expression in male and female chick embryos for at least six of nine Z chromosome genes . One Z-linked gene escaped compensation by this assay. Our results imply that the majority of Z-linked genes in the chicken are dosage compensated. The mechanism and extent of such avian dosage compensation remains unknown. We are using molecular and cytogenetic analyses of chicken Z chromosome in order to elucidate this question.
Dosage Compensation poster
Chicken Gynandromorph Analysis |  |
Despite the presence of ZW sex chromosomes in avian cells, their mechanism of sex-determination remains unknown. In collaboration with Mike Clinton of the Roslin Institute we are studying the biology and genetics of gynandromorph chickens which occur rarely and are characterised by the presence of both male and female physical characteristics.
Cancer Testes Gene methylation analysis |  |
Cancer testes (CT) genes are expressed in testes but not in somatic tissues, yet are often re-expressed in tumour cells. As a part of the collaborative "European Cancer Immunome Programe" we are investigating the methylation status of CT genes in relation to their expression.
We are currently analysing methylation status of several CT genes in germ-line, somatic and tumor materials. Preliminary evidence suggests the expression status of these genes to be associated with CpG methylation accross the promoter. Such a putative somatic biallelic methylation event is previously unreported. Further information on these genes can be found on the serex database.
Serex Data Base
