Townsend G
Hum Genet. 1982;61(3):267-8. doi: 10.1007/BF00296458.
Although the dentition of a 48,XYY,+21 male showed some typical features of Down's syndrome, metric analysis indicated a marked increase in tooth size particularly for early developing teeth. The extra Y chromosome can influence phenotypic expression, overcoming the superimposed effects of the additional 21 chromosome.
虽然一名48,XYY,+21男性的牙列表现出一些唐氏综合征的典型特征，但测量分析表明牙齿尺寸显著增加，尤其是早期发育的牙齿。额外的Y染色体可影响表型表达，克服额外的21号染色体的叠加效应。
