Copy number variation of two separate regulatory regions upstream of SOX9 causes isolated 46,XY or 46,XX disorder of sex development.
J Med Genet
; 52(4): 240-7, 2015 Apr.
Article
in En
| MEDLINE
| ID: mdl-25604083
ABSTRACT
BACKGROUND:
SOX9 mutations cause the skeletal malformation syndrome campomelic dysplasia in combination with XY sex reversal. Studies in mice indicate that SOX9 acts as a testis-inducing transcription factor downstream of SRY, triggering Sertoli cell and testis differentiation. An SRY-dependent testis-specific enhancer for Sox9 has been identified only in mice. A previous study has implicated copy number variations (CNVs) of a 78 kb region 517-595 kb upstream of SOX9 in the aetiology of both 46,XY and 46,XX disorders of sex development (DSD). We wanted to better define this region for both disorders.RESULTS:
By CNV analysis, we identified SOX9 upstream duplications in three cases of SRY-negative 46,XX DSD, which together with previously reported duplications define a 68 kb region, 516-584 kb upstream of SOX9, designated XXSR (XX sex reversal region). More importantly, we identified heterozygous deletions in four families with SRY-positive 46,XY DSD without skeletal phenotype, which define a 32.5 kb interval 607.1-639.6 kb upstream of SOX9, designated XY sex reversal region (XYSR). To localise the suspected testis-specific enhancer, XYSR subfragments were tested in cell transfection and transgenic experiments. While transgenic experiments remained inconclusive, a 1.9 kb SRY-responsive subfragment drove expression specifically in Sertoli-like cells.CONCLUSIONS:
Our results indicate that isolated 46,XY and 46,XX DSD can be assigned to two separate regulatory regions, XYSR and XXSR, far upstream of SOX9. The 1.9 kb SRY-responsive subfragment from the XYSR might constitute the core of the Sertoli-cell enhancer of human SOX9, representing the so far missing link in the genetic cascade of male sex determination.Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Disorders of Sex Development
/
Regulatory Sequences, Nucleic Acid
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SOX9 Transcription Factor
/
DNA Copy Number Variations
Type of study:
Etiology_studies
/
Incidence_studies
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Observational_studies
/
Prognostic_studies
/
Risk_factors_studies
Limits:
Animals
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Female
/
Humans
/
Male
Language:
En
Journal:
J Med Genet
Year:
2015
Type:
Article
Affiliation country:
Germany