Eastman J, Bixler D
J Craniofac Genet Dev Biol. 1982;2(1):35-44.
This report concerns a family showing both the lethal and mild form of hypophosphatasia in half-sibs. In addition, several other paternal family members with the mild form are documented. The lethal form is characterized by extremely low to absent alkaline phosphatase activity in serum with hypomineralization of the skeleton, whereas mildly affected individuals have enzyme levels intermediate between normal and lethal states. On the basis of this pedigree and because the mildly affected individuals have both biochemical abnormalities and the clinical phenotype of premature tooth loss, we prefer to designate hypophosphatasia as a dominant trait affecting both osteogenesis and cementogenesis which has mild clinical expression in the heterozygote but lethality in the homozygote. This situation resembles the dominantly inherited enzymopathy acute intermittent porphyria.
本报告涉及一个半同胞中同时出现致死型和轻型低磷酸酯酶症的家族。此外，还记录了其他几位患有轻型病症的父系家族成员。致死型的特征是血清中碱性磷酸酶活性极低或缺失，同时骨骼矿化不足，而症状较轻的个体酶水平介于正常和致死状态之间。基于这个家系，并且由于症状较轻的个体既有生化异常又有早发性牙齿脱落的临床表型，我们倾向于将低磷酸酯酶症认定为一种影响成骨和牙骨质生成的显性性状，在杂合子中表现为轻度临床症状，在纯合子中则致死。这种情况类似于显性遗传的酶病急性间歇性卟啉症。
