van den Heuvel L, Op de Koul K, Knots E, Knoers N, Monnens L
Department of Pediatrics, University Hospital Nijmegen, The Netherlands.
Nephrol Dial Transplant. 2001 Jan;16(1):48-51. doi: 10.1093/ndt/16.1.48.
At present the genetic defect for autosomal recessive and autosomal dominant hypophosphataemic rickets with hypercalciuria (HHRH) is unknown. Type II sodium/phosphate cotransporter (NPT2) gene is a serious candidate for being the causative gene in either or both autosomal recessive and autosomal dominant HHRH. In the present study we tested this hypothesis in one autosomal recessive family.
The gene structure of human NPT2 is known. We tested the complete open reading frame in the affected siblings by polymerase chain reaction in combination with automatic DNA sequencing for the presence of mutations.
We did not observe disease-causing mutations in the NPT2 gene of the affected siblings. A T855C polymorphism resulting in a histidine to arginine transition was present in the open reading frame of NPT2. The polymorphism was present in both affected as well as unaffected family members.
The hypothesis that a defect in the NPT2 gene could be an underlying cause for autosomal recessive HHRH could not be sustained in our study.
目前，伴有高钙尿症的常染色体隐性和显性低磷血症佝偻病（HHRH）的基因缺陷尚不清楚。II型钠/磷协同转运蛋白（NPT2）基因是常染色体隐性和显性HHRH致病基因的重要候选基因。在本研究中，我们在一个常染色体隐性遗传家系中验证了这一假说。
已知人类NPT2的基因结构。我们通过聚合酶链反应结合自动DNA测序，检测患病同胞的完整开放阅读框中是否存在突变。
我们在患病同胞的NPT2基因中未观察到致病突变。在NPT2的开放阅读框中存在一个T855C多态性，导致组氨酸向精氨酸转变。该多态性在患病和未患病的家庭成员中均存在。
在我们的研究中，NPT2基因缺陷可能是常染色体隐性HHRH潜在病因的假说无法得到支持。
