Disorders of sex development (DSD) represent a diverse group of clinical conditions, which have a very wide phenotypic spectrum associated with a complicated molecular background. Such conditions are considered among the most common birth defects and are frequently associated with congenital abnormalities.
Herein we present 66 patients with DSD associated with somatic anomalies, who were selected from clinical genetics dept., NRC. The patients underwent detailed clinical and genital assessment, Quigley scoring of external genitalia, pubertal staging, hormonal profiling, and imaging analysis. Chromosomal analysis of the peripheral blood lymphocytes was performed using GTG banding technique for all patients. FISH analysis was performed whenever indicated. MLPA was carried out for selected patients and chromosomal microarray (CMA) were conducted for 15 patients.
12 patients had numerical sex chromosomal abnormalities of them 3 had a translocation of a sex chromosome to an autosome; 13 patients had autosomal abnormalities; 25 patients had 46,XY karyotype, of them 8 were clinically diagnosed as having recognizable syndromes; 19 patients had 46,XX karyotype, one of them was clinically diagnosed as having Rubinstein Taybi syndrome. CMA detected significant copy number abnormalities in 7 patients, which were correlated to the phenotype.
The study emphasizes the crucial need to improve the clinical utility of genetic analysis in patients with DSD. CMAs can dramatically assist diagnosis in patients with multiple anomalies, not specific to a well-delineated genetic syndrome, and help more understanding of the molecular basis of DSD.
Improving the diagnostic yield for such complicated disorders will be reflected on the patients and their families, regarding possible therapeutic interventions, recurrence risk and carrier detection.
Dr. Mona Kamal Mekkawy, associate professor of Human genetics, Human Cytogenetics department , National Research Centre (NRC), Cairo, Egypt. Graduated in the Faculty of Medicine, Ain Shams University. Had M.Sc. degree in Pediatrics, Ain Shams University and PhD in Human Genetics, Alexandria University. Major research interests are: human cytogenetics and molecular cytogenetics and its recent diagnostic applications in human genetics, especially experienced in the field of disorders of sex development (DSD).
Supervised many MSc. and PhD thesis for student from National Research Centre and Cairo university in the field of chromosomal disorders in DSD patients, gonadal tissue culture, FISH analysis and microdeletion detection by MLPA techniques and copy number variation detection by chromosomal microarray. In addition to micronucleus assays for DNA damage detection.
Experienced practical teaching in many training courses held in the human cytogenetics dept. Also participated as a speaker in many courses and lectures carried out in the department and in the division of human genetics and genome research and in many activities and courses held in NRC and in other Egyptian universities.