Increasing role of cytogenetics in pediatric practice.

TLDR: It is suggested that cytogenetic analysis is useful in the investigation of children with genetic disorders of unknown origin to confirm clinical diagnosis and to allow for proper genetic counseling.

Abstract: Karyotyping was done in 100 children suspected of having chromosomal abnormalities of genetically uncertain syndromes, multiple congenital anomalies, short stature, dysmorphic features, unclassified mental retardation, and Down syndrome. A total of 56 patients had an abnormal karyotype: ring chromosome of 13 was seen in 1 patient (1.78%), and trisomy 21 was seen in 29 patients (51.78%) who were diagnosed as Down syndrome patients. Among them, 9 were male patients (31.03%) (47,XY+21) and 18 were female patients (47,XX+21) (62.06%); 2 patients showed 47,XY+21/46,XY (mosaicism) (6.89%). Chromosomal rearrangements involving chromosome numbers 13, 14, and 21 were seen in three patients. Among them, one patient had t(13;21) [45,XX,t(13;21)] and two patients had 45,XY,t(14;21). Trisomy 22 was seen in three patients (5.3%), marker chromosome was seen in two patients (3.57%), 46,XY,16qh variant was seen in one patient (1.78%), 46,XX,der(2) was seen in one patient (1.78%), 46,XX,14ps+ was seen in two patients (3.57...