Novel CYP27B1 Gene Mutations in Patients with Vitamin D-Dependent Rickets Type 1A.

Bibliographic Details
Title: Novel CYP27B1 Gene Mutations in Patients with Vitamin D-Dependent Rickets Type 1A.
Authors: Korcan Demir, Walaa E Kattan, Minjing Zou, Erdem Durmaz, Huda BinEssa, Özlem Nalbantoğlu, Roua A Al-Rijjal, Brian Meyer, Behzat Özkan, Yufei Shi
Source: PLoS ONE, Vol 10, Iss 7, p e0131376 (2015)
Publisher Information: Public Library of Science (PLoS), 2015.
Publication Year: 2015
Collection: LCC:Medicine
LCC:Science
Subject Terms: Medicine, Science
More Details: The CYP27B1 gene encodes 25-hydroxyvitamin D-1α-hydroxylase. Mutations of this gene cause vitamin D-dependent rickets type 1A (VDDR-IA, OMIM 264700), which is a rare autosomal recessive disorder. To investigate CYP27B1 mutations, we studied 8 patients from 7 unrelated families. All coding exons and intron-exon boundaries of CYP27B1 gene were amplified by PCR from peripheral leukocyte DNA and subsequently sequenced. Homozygous mutations in the CYP27B1 gene were found in all the patients and heterozygous mutations were present in their normal parents. One novel single nucleotide variation (SNV, c.1215 T>C, p.R379R in the last nucleotide of exon 7) and three novel mutations were identified:, a splice donor site mutation (c.1215+2T>A) in intron 7, a 16-bp deletion in exon 6 (c.1022-1037del16), and a 2-bp deletion in exon 5 (c.934_935delAC). Both c.1215 T>C and c.1215+2T>A were present together in homozygous form in two unrelated patients, and caused exon 7 skipping. However, c.1215 T>C alone has no effect on pre-mRNA splicing. The skipping of exon 7 resulted in a shift of downstream reading frame and a premature stop codon 57 amino acids from L380 (p.L380Afs*57). The intra-exon deletions of c.1022-1037del16 and c.934_935delAC also resulted in a frameshift and the creation of premature stop codons at p.T341Rfs*5, and p.T312Rfs*19, respectively, leading to the functional inactivation of the CYP27B1 gene. Clinically, all the patients required continued calcitriol treatment and the clinical presentations were consistent with the complete loss of vitamin D1α-hydroxylase activity. In conclusion, three novel mutations have been identified. All of them caused frameshift and truncated proteins. The silent c.1215 T>C SNV has no effect on pre-mRNA splicing and it is likely a novel SNP. The current study further expands the CYP27B1 mutation spectrum.
Document Type: article
File Description: electronic resource
Language: English
ISSN: 1932-6203
Relation: http://europepmc.org/articles/PMC4489500?pdf=render; https://doaj.org/toc/1932-6203
DOI: 10.1371/journal.pone.0131376
Access URL: https://doaj.org/article/e3903ac1b8b24c278d67482cbfa3e096
Accession Number: edsdoj.3903ac1b8b24c278d67482cbfa3e096
Database: Directory of Open Access Journals
More Details
ISSN:19326203
DOI:10.1371/journal.pone.0131376
Published in:PLoS ONE
Language:English