Body and craneofacial measurements for defining criteria of phenotypic variation in Down's syndrome

Abstract

Twenty four five year old male children with full 21 trisomy syndrome, without congenital heart anomalies, and twenty four healtly children of the same age and sex, as controls, were studied, in order to define the direct measurements that permit discriminating between Down’s syndrome (DS) and no Down syndrome (NDS), to characterize those with DS, to find the differences with the NDS ones, to determine DS subgroups and to compare the observations of the clinicians. Thirty seven direct measurements of head, face, trunk, upper and lower limbs were performed. Out of them three classified and separated DS and NDS children (100%). Five observations performed by clinicians only discriminate 79,1% of the DS children. In the DS children, by grouping the variables, five subgroups were detected; only one of these included the variables used by the clinicians, namely: weight, leg length, hand length, ear width, helix width and nasal index in DS and weigth, helix width and nasal index in NDS had the higher variation coefficient. DS children have lesser weight and size.