Stoll C, Fischbach M, Terzic J, Alembik Y, Vuillemin M O, Mornet E
Service de Génétique Médicale, Centre Hospitalo-Universitaire, Strasbourg, France.
Genet Couns. 2002;13(3):289-95.
Hypophosphatasia is a rare autosomal recessive inborn error of metabolism characterized by a defective bone mineralisation and deficiency of serum and tissue liver/bone/kidney alkaline phosphatase activity. We report the characterisation of tissue-nonspecific alkaline phosphatase (TNSALP) gene mutation in a patient affected by infantile hypophosphatasia. This boy was the first child of non affected, non related parents. At 1 month of age he presented with palsy of the left upper limb with hypotonia. Length was - 2SD. The anterior fontanel was large. There was a markedly decreased ossification of all bones. All limbs were shortened. Ultrasonographic examination of the kidneys showed nephrocalcinosis. Level of alkaline phosphatases was decreased in the child as well as in the parents. Bone density was decreased. At 2 years of age development was delayed. Weight was - 3,5 SD and OFC - 3SD. The child had craniosynostosis. Molecular studies showed 2 missense mutations, both in exon 6 of the TNSALP gene.
低磷酸酯酶症是一种罕见的常染色体隐性遗传代谢病，其特征为骨矿化缺陷以及血清和组织肝/骨/肾碱性磷酸酶活性缺乏。我们报告了一名患婴儿型低磷酸酯酶症患者的组织非特异性碱性磷酸酶（TNSALP）基因突变特征。这个男孩是父母的第一个孩子，父母未受影响且无亲缘关系。1月龄时，他出现左上肢麻痹伴肌张力减退。身长低于均值2个标准差。前囟门大。所有骨骼的骨化明显减少。所有肢体均短小。肾脏超声检查显示肾钙质沉着症。患儿及其父母的碱性磷酸酶水平均降低。骨密度降低。2岁时发育迟缓。体重低于均值3.5个标准差，头围低于均值3个标准差。患儿患有颅骨缝早闭。分子研究显示，TNSALP基因外显子6存在2个错义突变。
