Details

Autor(en) / Beteiligte

• Ambrose, H J
• Chambers, S M
• Mieli-Vergani, G
• Ferrie, R
• Newton, C R
• Robertson, N H

Titel

Molecular characterization of a new alpha-1-antitrypsin M variant allele, Mwhitstable: implications for DNA-based diagnosis

Ist Teil von

• Diagnostic molecular pathology, 1999-12, Vol.8 (4), p.205-210

Ort / Verlag

United States

Erscheinungsjahr

1999

Quelle

MEDLINE

Beschreibungen/Notizen

• The mother and second child from a family, already with one PI ZZ child, were typed PI MZ by isoelectric focusing and unexpectedly as PI ZZ using a commercial alpha-1-antitrypsin genotyping kit. Both methods typed the father and first child as PI MZ and PI ZZ, respectively. DNA sequence analysis identified a 26-base pair (bp) deletion and 2-bp insertion in intron IV of the normal PI*M allele from both the mother and second child. The majority of the binding site for an amplification primer of the genotyping kit was absent in the variant deletion-insertion allele. The apparent PI*Z/PI*Z genotype of the mother and second child therefore arose from amplification of the PI*Z allele alone. Two hundred random DNA samples were subsequently examined and 5 of these were found to be heterozygous for the same deletion-insertion allele. The authors have designated the previously undescribed PI*M allele that harbors this benign polymorphism PI*Mwhitstable. The genotyping kit has been redesigned and revalidated, and its performance is not affected by the presence of the PI*Mwhitstable allele. The Gen Bank accession number for the nucleotide sequence described is AF159454.