Kloepfer H W, Parisi P
Acta Genet Med Gemellol (Roma). 1976;25:177-80. doi: 10.1017/s0001566000014082.
Among 59 sets of MZ male twins and 48 sets of MZ female twins from Italy, 7 male sets (11.9%) and 7 female sets (14.6%) had absent c-triradius on one or more palms; among 214 individuals who had a MZ twin, 19(8.9%) had absent c-triradius in one or both palms. Due to small numbers these percentages are comparable to the occurrence of absent c-triradius found in 8.2% of 3946 Caucasians. When one member of a set of MZ twins showed the trait in one or both palms, 35.7% (5/14) of the other members also showed the trait in one or both palms. When an individual showed the trait in one palm, 26.3% (5/19) of the other palms also showed the trait. These two estimates of penetrance combined give an average value of 30.3% (10/33) which is comparable to an estimate of 30% found in a study of 478 family units in which transmission was compatible with an autosomal dominant gene.
在来自意大利的59对男性同卵双胞胎和48对女性同卵双胞胎中，7对男性双胞胎（11.9%）和7对女性双胞胎（14.6%）的一只或多只手掌上没有c三叉点；在有同卵双胞胎的214个人中，19人（8.9%）的一只或两只手掌上没有c三叉点。由于数量较少，这些百分比与在3946名高加索人中8.2%的无c三叉点发生率相当。当一对同卵双胞胎中的一个成员在一只或两只手掌上表现出该特征时，其他成员中有35.7%（5/14）也在一只或两只手掌上表现出该特征。当一个人在一只手掌上表现出该特征时，另一只手掌中有26.3%（5/19）也表现出该特征。这两个外显率估计值相结合得出的平均值为30.3%（10/33），这与在一项对478个家族单位的研究中发现的30%的估计值相当，在该研究中，遗传传递符合常染色体显性基因。
