Identification of mutations in the SRD5A2 gene in Thai patients with male pseudohermaphroditism.
OBJECTIVE
To describe two unrelated Thai patients with suspected 5alpha-reductase type 2 deficiency and perform mutation analysis of the SRD5A2 gene.


METHODS
Case report.


METHODS
A pediatric endocrinology clinic at a university hospital.


METHODS
Two unrelated patients with 46,XY karyotype, born with ambiguous genitalia, were studied. One was reared as a boy and the other was reared as a girl.


METHODS
The entire coding regions of the SRD5A2 gene were assessed by polymerase chain reaction (PCR) and sequencing analysis.


METHODS
Molecular characterization of the SRD5A2 gene.


RESULTS
Four different pathogenic mutations (three missense and one nonsense) were identified. These were located at exon 1 (p.Q6X and p.L20P), exon 3 (p.G183S), and exon 4 (p.G203S). The T>C transition (c.59T>C) resulting in a leucine-to-proline substitution at codon 20 (p.L20P) has not been previously described and was not detected in 100 unaffected, ethnic-matched control chromosomes. In addition, p.G183S, previously identified only among patients from mixed African-European ancestry and in the Dominican Republic, was also detected in a Thai patient.


CONCLUSIONS
This study demonstrates that the SRD5A2 gene is responsible for 5alpha-reductase type 2 deficiency across different populations and emphasizes the important role of genetic testing for the definite diagnosis and genetic counseling before gender assignment or any surgical intervention.
Sahakitrungruang
Taninee
T
Department of Pediatrics, Division of Pediatric Endocrinology, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand.
Wacharasindhu
Suttipong
S
Yeetong
Patra
P
Snabboon
Thiti
T
Suphapeetiporn
Kanya
K
Shotelersuk
Vorasuk
V
D013741:3-Oxo-5-alpha-Steroid 4-Dehydrogenase / Q000235:genetics*; D000595:Amino Acid Sequence; D004252:DNA Mutational Analysis; D012734:Disorders of Sex Development / Q000201:enzymology / Q000235:genetics* / Q000473:pathology; D005260:Female; D020022:Genetic Predisposition to Disease; D006066:Gonads / Q000473:pathology; D006801:Humans; D008297:Male; D008969:Molecular Sequence Data; D009154:Mutation; D013785:Thailand
D013741:3-Oxo-5-alpha-Steroid 4-Dehydrogenase