Identification and characterization of two novel mutations that produce acute intermittent porphyria: A 3-base deletion (841-843delGGA) and a missense mutation (T35M)

Hum Mutat. 2000 Oct;16(4):373. doi: 10.1002/1098-1004(200010)16:4<373::AID-HUMU14>3.0.CO;2-A.

Abstract

A partial deficiency of Porphobilinogen deaminase (PBGD) is responsible for acute intermittent porphyria (AIP). AIP is inherited in an autosomal dominant fashion, and the prevalence in the Argentinean population is about 1:125,000. Here, two new mutations and two previously reported were found in the PBGD gene in 22 Argentinean AIP patients corresponding to 8 different families. To screen for AIP mutations in symptomatic patients, genomic DNA isolated was amplified in 6 PCR reactions, then all coding exons and flanking intronic regions were sequenced. The novel mutations are 841-843delGGA in exon 14, which results in the loss of glycine-281 (G281del), and one 104C>T point mutation in the exon 4 (T35M). To further characterize both novel mutations, the pKK-PBGD construct for the mutant alleles were expressed in E. coli, the enzymatic activity of the recombinant proteins were 1% and 4% of the mean level expressed by the normal allele for 841-843delGGA and T35M, respectively. Hum Mutat 16:373, 2000.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Child
  • Female
  • Humans
  • Hydroxymethylbilane Synthase / genetics*
  • Male
  • Methionine / genetics
  • Middle Aged
  • Mutation, Missense / genetics*
  • Porphyria, Acute Intermittent / enzymology*
  • Porphyria, Acute Intermittent / genetics*
  • Sequence Deletion / genetics*
  • Threonine / genetics

Substances

  • Threonine
  • Methionine
  • Hydroxymethylbilane Synthase