Arbour L, Watters G V, Hall J G, Fraser F C
Department of Human Genetics, McGill University, Montreal, Quebec, Canada.
Clin Genet. 1996 Aug;50(2):57-62. doi: 10.1111/j.1399-0004.1996.tb02349.x.
To reevaluate previous claims that non-syndromic macrocephaly is usually inherited as an autosomal dominant trait.
Head size was measured in the parents and sibs of children with non-syndromic macrocephaly.
If autosomal dominant inheritance is involved, the frequency distribution should be bimodal.
Head circumference of parents and sibs of the macrocephalic probands had a mean significantly greater than the population norm, and a unimodal distribution. Probands with psychomotor impairment had bigger heads, and more had a history of birth difficulty, than did unimpaired probands.
The usual genetic basis for non-syndromic macrocephaly is multifactorial with a polygenic genetic basis, rather than autosomal dominant. Risk of recurrence appears to be much lower than if it would be on the assumption of autosomal dominant inheritance. Macrocephaly in a parent or sib of an unborn child may present a risk for birth injury to that child. A larger series of patients will be necessary to resolve this question.
重新评估先前关于非综合征性巨头畸形通常作为常染色体显性性状遗传的说法。
对非综合征性巨头畸形儿童的父母及同胞的头围进行测量。
若涉及常染色体显性遗传，频率分布应为双峰型。
巨头畸形先证者的父母及同胞的头围均值显著高于总体正常水平，且呈单峰分布。与未受损的先证者相比，有精神运动障碍的先证者头部更大，且更多有出生困难史。
非综合征性巨头畸形常见的遗传基础是多因素的，具有多基因遗传基础，而非常染色体显性遗传。复发风险似乎比基于常染色体显性遗传假设时要低得多。未出生孩子的父母或同胞中的巨头畸形可能会给该孩子带来出生损伤风险。需要更大样本量的患者系列来解决这个问题。
