Herein we characterize an apparently balanced de novo translocation, 
t(X;15)(p22.2;q26.1)dn, in a female patient with scoliosis, hirsutism, learning 
problems, and developmental delay (DGAP025). Other clinical findings include a 
high-arched palate, 2-3 syndactyly of the toes, and mildly elevated serum 
testosterone. No known or predicted genes are disrupted by the Xp22.2 
breakpoint. The 15q26.1 breakpoint disrupts chromodomain helicase DNA binding 
protein 2 (CHD2). Another member of the chromatin-remodeling gene family, CHD7, 
has been associated with a defined constellation of congenital anomalies known 
as coloboma, heart anomaly, choanal atresia, mental retardation, genital and ear 
anomalies syndrome (CHARGE) and idiopathic scoliosis. Monosomy of 15q26 also has 
been associated with a spectrum of congenital abnormalities and growth 
retardation that overlaps with those of DGAP025. To provide a biological 
correlate, we characterized a mutant mouse model with Chd2 disruption that is 
associated with embryonic and perinatal lethality. Expression analysis indicated 
that Chd2 is expressed in the heart, forebrain, extremities, facial and dorsal 
regions during specific times of embryonic development. Chd2(+/m) mice showed 
pronounced lordokyphosis, reduced body fat, postnatal runting, and growth 
retardation. These data suggest that haploinsufficiency for CHD2 could result in 
a complex of abnormal human phenotypes that includes scoliosis and possibly 
features similar to CHARGE syndrome.