Distal trisomy of the long arm of chromosome 10 results in characteristics of pre and postnatal growth retardation, a pattern of specific facial features, hypotonia, and developmental and psychomotor delay. To date, approximately 40 cases have been reported. Most cases are diagnosed in infancy or in childhood. The range and severity of symptoms and physical findings may vary from case to case, depending upon the exact length and location of the duplicated portion of chromosome 10q. The duplicated region almost always includes 10qter, with the most frequent proximal breakpoint at 10q24 (with variation from q22 to q25). Interstitial duplications of 10q have also been reported. [from
SNOMEDCT_US]