A splicing mutation in the cytochrome b5 gene from a patient with congenital methemoglobinemia and pseudohermaphrodism.

Abstract

We have analyzed reticulocyte and leukocyte mRNAs isolated from a patient with congenital methemoglobinemia and pseudohermaphrodism. The cytochrome b5 cDNA sequences were amplified using specific oligonucleotide primers and the polymerase chain reaction (PCR). DNA sequencing indicated that there was a 16-bp deletion in the cDNA leading to a new, in-frame stop signal and resulting in a truncated protein of 45 amino acids. Genomic DNA was analyzed, and the molecular lesion was shown to be an AG-->GG alteration in the 3' splicing junction of intron 1. The splice site alteration leads to the usage of the nearest AG as an alternative splice site, resulting in a 16-bp deletion in the mRNA. All of the studies on reticulocyte mRNA and genomic DNA indicated that the patient was homozygous for the lesion.

• Authors: S J Giordano, A Kaftory, A W Steggles
• Journal: Human genetics (Hum Genet) Vol. 93 Issue 5 Pg. 568-70 (May 1994) ISSN: 0340-6717 [Print] Germany
• PMID: 8168836 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• DNA Primers
• DNA, Recombinant
• RNA, Messenger
• Cytochromes b5

Topics

• Base Sequence
• Cytochromes b5 (genetics)
• DNA Primers (chemistry)
• DNA, Recombinant
• Disorders of Sex Development (enzymology, genetics)
• Gene Deletion
• Humans
• Leukocytes (metabolism)
• Male
• Methemoglobinemia (congenital, enzymology)
• Molecular Sequence Data
• Mutation
• Polymerase Chain Reaction
• RNA, Messenger (metabolism)
• Reticulocytes (metabolism)