Trisomy 21, caused by triplication of human chromosome 21, is also known as Down syndrome (DS) and affects every 1 out of 800 births. DS causes morphometric deviations in the brain and face as well as behavioral changes, due to gene dosage imbalances. Since many DS studies focus on adults, there are very few that explore how DS influences children. This investigation helps to fill this void in the literature by seeking to understand the differences in brain morphometry in children with DS and euploid controls. To do this, we first obtained two age- and gender-matched sample groups composed of MRI images from 1) children with DS (n=31 images, 0-4 yrs.); 2) euploid children (n = 31 images, 0-4 yrs.). MRI images were provided by the Florida Hospital (now AdventHealth) and the National Institute of Health. On these MRI images, 36 anatomical landmarks were placed throughout the brain. With the 36 landmarks, Euclidean Distance Matrix Analysis was used to measure every unique linear distance between landmarks, resulting in a total of 630 linear distances. Out of 630 linear distances, 211 (33.49%) were significantly different between the two samples (p-value < 0.05), as determined by analysis of variance (ANOVA) calculations. From these 211 linear distances, 22 were extremely different between the two samples (p-value < 0.001) and were thoroughly analyzed. Based on our results, regions of the brain that were significantly different in children with DS include the following: frontal lobe, occipital lobe, ventricles, thalamus, striatum, and corpus callosum. Such morphometric changes are likely associated with behavioral changes such as social-cognitive defects and motor-related issues commonly seen in DS.
Bachelor of Science (B.S.)
College of Medicine
Length of Campus-only Access
Ahmad, Yaser, "The Analysis of the Impact of Trisomy 21 on Brain Morphometry in Humans" (2019). Honors Undergraduate Theses. 597.