trisomy 18 syndrome
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Related to trisomy 18 syndrome: Edwards syndrome
trisomy 18 syndrome[′trī‚sō·mē ′ā¦tēn ‚sin‚drōm]
A congenital disorder due to trisomy of all or a large part of chromosome 18, characterized by severe mental deficiency, hypertonicity with clenched hands, and anomalies of the hands, sternum, pelvis, and facies; most infants so afflicted fail to thrive. Also known as Edwards' syndrome; E trisomy.