title: Altered SOX9 genital tubercle enhancer region in hypospadias.
abstract: Human mutations in the SOX9 gene or its regulatory region can disrupt testicular development, leading to disorders of sex development (DSDs). Our previous work involving the genomic analysis of isolated DSD patients revealed a 78kb minimal sex determining region (RevSex) far upstream of SOX9 that was duplicated in 46,XX and deleted in 46,XY DSDs. It was postulated that RevSex contains a gonadal enhancer. However, the most highly conserved sub-region within RevSex, called SR4, was neither responsive to sex determining factors in vitro nor active in the gonads of transgenic mice, suggesting that SR4 may not be functioning as a testicular enhancer. Interestingly, SR4 transgenic mice showed reporter activity in the genital tubercle, the primordium of the penis and clitoris, a previously unreported domain of Sox9 expression. SOX9 protein was detected in the genital tubercle, notably in the urethral plate epithelium, preputial glands, ventral surface ectoderm and corpus cavernosa. SR4 may therefore function as a Sox9 genital tubercle enhancer, mutations of which could possibly lead to hypospadias, a birth defect seen in the DSD patients in the RevSex study. SR4 activity and the observed SOX9 expression pattern suggest that SR4 may function as a Sox9 genital tubercle enhancer. However, conditional ablation of Sox9 in the genital tubercle using Shh-Cre/+;Sox9flox/floxmice revealed no genital tubercle abnormalities, possibly due to compensation by similar Sox factors. To conclude, we have identified a novel regulatory enhancer driving Sox9 expression during external genitalia development.
authors.affiliation: Molecular Genetics and Development, Hudson Institute of Medical Research, Melbourne, Victoria, Australia; Department of Anatomy and Neuroscience, University of Melbourne, Melbourne, Victoria, Australia; Monash University, Melbourne, Victoria, Australia.
authors.forename: Rajini
authors.initials: R
authors.lastname: Sreenivasan
authors.affiliation: Laboratory of Embryology and Genetics of Congenital Malformations, Institut National de la Santé et de la Recherche Médicale (INSERM) U1163, Institut Imagine, Paris, France; Paris Descartes-Sorbonne Paris Cité University, Institut Imagine, Paris, France.
authors.forename: Christopher T
authors.initials: CT
authors.lastname: Gordon
authors.affiliation: Laboratory of Embryology and Genetics of Congenital Malformations, Institut National de la Santé et de la Recherche Médicale (INSERM) U1163, Institut Imagine, Paris, France; Paris Descartes-Sorbonne Paris Cité University, Institut Imagine, Paris, France.
authors.forename: Sabina
authors.initials: S
authors.lastname: Benko
authors.affiliation: Department of Anatomy and Neuroscience, University of Melbourne, Melbourne, Victoria, Australia.
authors.forename: Robb
authors.initials: R
authors.lastname: de Iongh
authors.affiliation: Molecular Genetics and Development, Hudson Institute of Medical Research, Melbourne, Victoria, Australia; Monash University, Melbourne, Victoria, Australia.
authors.forename: Stefan
authors.initials: S
authors.lastname: Bagheri-Fam
authors.affiliation: Laboratory of Embryology and Genetics of Congenital Malformations, Institut National de la Santé et de la Recherche Médicale (INSERM) U1163, Institut Imagine, Paris, France; Paris Descartes-Sorbonne Paris Cité University, Institut Imagine, Paris, France.
authors.forename: Stanislas
authors.initials: S
authors.lastname: Lyonnet
authors.affiliation: Molecular Genetics and Development, Hudson Institute of Medical Research, Melbourne, Victoria, Australia; Monash University, Melbourne, Victoria, Australia. Electronic address: vincent.harley@hudson.org.au.
authors.forename: Vincent
authors.initials: V
authors.lastname: Harley
mesh_terms: D000818:Animals; D002460:Cell Line; D005260:Female; D005836:Genitalia, Female; D005838:Genotype; D006801:Humans; D007021:Hypospadias / Q000235:genetics*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D008822:Mice, Transgenic; D009154:Mutation; D012045:Regulatory Sequences, Nucleic Acid / Q000235:genetics*; D055758:SOX9 Transcription Factor / Q000235:genetics*
chemical_list: D055758:SOX9 Transcription Factor; C527932:SOX9 protein, human; C527933:Sox9 protein, mouse
keywords: Disorder of sex development; Enhancer; Genital tubercle; Hypospadias; SOX9