ESPE Abstracts

Background: Deletions of distal chromosome 9p24 are often associated with 46,XY gonadal dysgenesis and, depending on the extent of the deletion, the monosomy 9p syndrome. The phenotype shows variable expressivity and is related to the size of the deletion. XY sex reversal is a relatively rare type of DSD (disorder of sexual development). Terminal region of short arm chromosome 9p (9p24.3 region) contains 3 types of DMRT genes (DMRT1-3). DMRT1 gen acts in synergy with SRY gen and has an important role in sex differentiation. We report a -12 month-old phenotypically female baby this rare disease.

Case report: A 12-month-old female patient was referred to our to our clinic because of a dysmorphic appearance and hypotonia. The proband was born at full term to a 28-year-old female, from uncomplicated pregnancy by cesarean delivery. She is the first-born child. There was no family history of endocrine and genetic disorders or consanguinity. Birth lenght was 53 cm (50 Percentile). Birth weight was 3360 g (50 Percentile). She was hospitalized in the neurology department at the age of eight months due to hypotonia and delayed psychomotor development. At her physical examination at 12 months of age, her height, weight were 74 cm (50th centile), 9500 g (25th-50th centile). She had a flat occiput, high forehead, hypertelorism, posteriorly angulated ears, small nose, full cheeks, short and broad neck, widely spaced nipples and severe hypotonia. On her external genitalia examination, normal female external genitalia was observed. She was referred for karyotyping due hypotonia, delayed psychomotor development, and possible spinal muscular atrophy. Karyotyping results showed 46,XY(50%)/ 47,XY+mar. Labaratory findings showed normal thyroid hormones, normal estrogen and low testosterone (< 0.10ng/ml). Gonads were unclear on pelvic ultrasonography. Pelvic magnetic resonance imaging (MRI) findings indicated a normal-sized uterus, while the adnexal structure imaging was unclear. Child underwent genetic investigations. Microarray analysis showed deletion 9p24.3-p23p.

Conclisons: In conclusion, we report a case with contralateral 46,XY DSD, which is extremely rare, in whom was detected deletion of the DMRT gene cluster that is responsible for DSD. It is important to have a multidisciplinary team for management and follow-up with these patients for an adequate sex assignment and treatment for any complications associated to the syndrome, if possible, in order to have a better quality of life.