The findings in this study suggest that in patients with FHR, circulating PTH is required for the genetically transmitted abnormality to be physiologically expressed as a reduction in net renal reabsorption of phosphate, and that this physiological expression of the genetic abnormality is expressed fully at normal or nearly normal circulating levels of PTH.
Mutation at a locus (HPDR) on the X chromosome (McKusick 30780 [HPDR1]; 30781 [HPDR2]) causes impaired renal phosphate transport, hypophosphatemia, and an associated impairment in the process of mineralization in bone and teeth (X-linked hypophosphatemia [XLH]).
Mutation at a locus (HPDR) on the X chromosome (McKusick 30780 [HPDR1]; 30781 [HPDR2]) causes impaired renal phosphate transport, hypophosphatemia, and an associated impairment in the process of mineralization in bone and teeth (X-linked hypophosphatemia [XLH]).
These results imply that the Hyp gene is expressed in situ in renal epithelium and suggest that humoral factors are not necessary for the mutant renal phenotype in X-linked hypophosphatemia of mouse and man.
We have measured circulating osteocalcin levels in 10 patients with x-linked hypophosphatemia (XLH) and in 6 patients with autosomal recessive vitamin D dependence (ARVDD) who started 1,25-dihydroxyvitamin D3 [1,25-(OH)2D3] therapy.
Intragenic non-overlapping deletions from four different families and three mutations (two splice sites and one frameshift) have been detected in HYP patients, which suggest that the PEX gene is involved in the HYP disorder.
DNA polymorphism analysis of the Bc1I site of exons 17-18 of factor VIII gene of the woman and her last two fetuses seemed to be compatible with a linkage between the XLH locus and factor VIII gene.
Our data indicate that DXS365, DXS3424, DXS443, DXS1052, DXS274, and DXS1683 are tightly linked to the HYP gene and suggest a locus order of: Xtel-DXS315-(GLR/DXS43)-DXS257-(DXS443+ ++-DXS3424)-DXS365-HYP-DXS1683-DXS1052-DXS 274-(DXS41/DXS92)-DXS451-Xcen.
Our data indicate that DXS365, DXS3424, DXS443, DXS1052, DXS274, and DXS1683 are tightly linked to the HYP gene and suggest a locus order of: Xtel-DXS315-(GLR/DXS43)-DXS257-(DXS443+ ++-DXS3424)-DXS365-HYP-DXS1683-DXS1052-DXS 274-(DXS41/DXS92)-DXS451-Xcen.
These findings exclude NPT2 as a candidate gene for murine and human X-linked hypophosphatemias and suggest that genes at the Hyp, Gy and XLH (HYP) loci are involved in regulation of NPT2 gene expression.
We have examined the X inactivation pattern in peripheral blood cells from 12 females belonging to seven families with XLH using PCR analysis at the androgen receptor locus.
We conclude that Pex/PEX is a low-abundance transcript that is expressed predominantly in bone of mice and humans and that a large deletion in the 3' region of the Pex gene is present in the murine Hyp homologue of X-linked hypophosphatemia.
The aim of this study was to analyse 99 HYP families for PEX gene mutations, and to correlate predicted changes in the protein structure with Zn2+ metallopeptidase gene function.
The aim of this study was to analyse 99 HYP families for PEX gene mutations, and to correlate predicted changes in the protein structure with Zn2+ metallopeptidase gene function.
Although the entire PEX gene has not been identified and some mutations may have been missed, the lack of detection of mutations in the remaining 13 patients, especially in 1 patient who has an apparently balanced, de novo 9;13 translocation, implies that there may be other loci involved in the generation of the HYP phenotype.
Although the entire PEX gene has not been identified and some mutations may have been missed, the lack of detection of mutations in the remaining 13 patients, especially in 1 patient who has an apparently balanced, de novo 9;13 translocation, implies that there may be other loci involved in the generation of the HYP phenotype.