Azman BZ, Ankathil R, Siti Mariam I, Suhaida MA, Norhashimah M, Tarmizi AB, Nor Atifah MA, Kannan TP, Zilfalil BA
Correspondence: Dr Zilfalil BA, zilfalil@kb.usm.my
ABSTRACT
Introduction This study was designed to evaluate the karyotype pattern, clinical features and other systemic anomalies of patients with Down syndrome in Malaysia.
Methods Retrospective analysis was performed on the case records of 149 patients confirmed as Down syndrome by cytogenetic analysis at Human Genome Centre and Genetic Clinic at the Universiti Sains Malaysia.
Results Among the 149 cases of Down syndrome presenting over a period of 4.2 years, free trisomy (non-disjunction) was present in 141 cases (94.6 percent). One case (0.7 percent) had translocation, and seven cases (4.7 percent) were mosaics. Average age at presentation was 10.6 months. Average maternal age at birth of the affected child was 32.3 years. The prominent craniofacial features noted were upslanting palpebral fissures (89.3 percent), flat facial profile (64.9 percent), low set ears (56.1 percent), epicanthic folds (17.5 percent) and protruding tongue (19.2 percent). A total of 52.6 percent of the cases had documented hypotonia. Characteristic limb and dermatoglyphic anomalies included short stubby fingers (24.5 percent), sandal gap (33.3 percent), unilateral or bilateral simian crease (36.8 percent) and clinodactyly (19.2 percent). Ophthalmological abnormalities, such as hypertelorism, were presented in 33.3 percent of the cases. Congenital heart disease was diagnosed in 35 out of 71 cases (49.3 percent) and gastrointestinal anomalies were noted in 18 out of 79 cases (22.7 percent) analysed.
Conclusion Efforts to establish early diagnosis and a proper screening for high association with systemic anomalies should be undertaken among the Down syndrome patients in this population.
Keywords: cytogenetic analysis, Down syndrome, karyotype pattern, non-disjunction, trisomy 21
Singapore Med J 2007; 48(6): 550–554
