4.416667
#52
HIGH RESOLUTION HLA-DQA1 TYPING BY LiPA.
Ilse De Canck 1, Lia Verdoodt 1, Hilde De Henau 1, Nancy Vande Casteele 1, Miriam Blaser 2, John Harvey 3, Jane Bronham 3, Grant Davis 3, Tom Van De Casteele 4, Linda Celis 2 and Gonda Verpooten 1. 1 R&D, Innogenetics, Ghent, Belgium ; 2 Medical Affairs, Innogenetics, Ghent, Belgium ; 3 H&I Laboratory, NAtional Blood Service, Bristol, United Kingdom and 4 Statistics, Innogenetics, Ghent, Belgium .
A reverse hybridization assay, LiPA HLA-DQA1, has been developed for high resolution typing of HLA-DQA1 alleles. In order to identify the HLA-DQA1 alleles specifically in homozygous or heterozygous combinations, detection of polymorphisms in exons 1, 2 and 3 is required. Since this region is too large to amplify with one primer pair, a duplex PCR has been optimized, amplifying exon 1, and exons 2 and 3. After PCR, the amplicons are hybridized with 35 specific probes, immobilized on a single LiPA strip. For all HLA-DQA1 alleles described until April 2005 (IMGT-HLA database, release 2.9), 100 % theoretic allelic resolution is obtained.
In order to validate this assay, 79 samples previously DNA typed for HLA-DQA1 were typed by LiPA HLA-DQA1. All samples were successfully amplified and an interpretable result was obtained in all cases. Five discrepancies were present and were further analyzed by sequencing. The sequencing results confirmed the LiPA result.