The partners will agree upon a protocol for the investigation of 46,XY intersex patients and will share clinical, biological and genetic data or samples with the aim of increasing the proportion of successfully diagnosed patients and of identifying those in whom mutations of yet unknown genes are probably involved. Basic research will be focused on the identification of new genes involved in the sex determination and differentiation pathways. Somatic cell hybrids will be used to define the limits of deletions of chromosome 9p in sex-reversed patients. Hybrids will be tested for human chromosome 9 retention and hemizygosity, using microsatellite markers derived from non-deleted region of chromosome 9. The precise extent of the presently available 9p deletion will be defined and a radiation hybrid panel will be used to construct an integrated map of the deleted region. Screening of XY sex reversal patients for cryptic deletions may reduce further the region that includes the 9p sex reversal gene.. The relationship to DAX-1 and DAMs of sex-reversal genes present in a Xp21 critical interval will be investigated using the DNA of patients with an X-linked form of 46,XY sex reversal. In the event of negative results, new genes will be sought for in the critical interval. The Otwo hybrid yeast technology will be used to search for transcriptional activators of the human SRY gene. Identification of androgen-responsive genes will be carried out by differential display techniques in androgen-responsive cell lines and in fibroblasts derived from patients with androgen-insensitivity with a normal androgen receptor. Transcriptional activators of the androgen receptor will be studied using androgen-responsive reporter genes. An aromatase reporter gene will serve to set up an assay for transduction of the anti-Müllerian hormone signal. That system will be used to validate type I AMH receptor candidate clones after transfection in a permanent cell line expressing the type II receptor.
Funding SchemeCSC - Cost-sharing contracts
CB2 2QQ Cambridge
CB2 3EH Cambridge