Three patients with 9p deletions including DMRT1 and DMRT2: A girl with XY complement, bilateral ovotestes, and extreme growth retardation, and two XX females with normal pubertal development

It is well documented that distal 9p monosomy can be associated with XY sex reversal. Recently, the possibility of DMRT1 and/or DMRT2 (the genes for doublesex and mab-3 related transcription factor 1 and 2) being the sex determining genes(s) at 9p has been raised. DMRT1 and DMRT2 map near the 9p telomere, distal of marker D9S1779. We describe here three unrelated females with distal 9p monosomy, one with XY complement and two with XX complements. In each individual, fluorescent in situ hybridization predicted the loss of the DMRT genes. Patient 1, an XY individual with monosomy 9pter --> p24.1 approximately 24.2 and trisomy 7q32 --> qter had normal female external genitalia, a blind ending vagina, no uterus, a Fallopian tube on the right, and bilateral ovotestes with primitive ovarian tissue. She also had extreme growth retardation. Around 80 cases of distal 9p monosomy have been reported previously, but there has been no report of ovotestes or gonads comprising ovarian tissue in a XY patient with 9p deletion. Findings in Patient 1 suggest that the phenotypic spectrum of the heterozygous DMRT deletion may include true hermaphroditism. Patients 2 and 3 were 12- and 14-year-old females with XX complements, normal external genitalia, and normal pubertal development. Patient 2 had pure monosomy 9pter --> p23 and Patient 3 had monosomy 9pter --> p22.3 approximately 23 combined with trisomy 3pter --> p23 approximately 24. To date, detailed reports on the gonadal status of XX 9p-females have been limited to prepubertal girls. Patients 2 and 3 are the first females reported to have distal 9p monosomy and a normal puberty.