Effectiveness and limitations of resolving HLA class I and class II by heterozygous ambiguity resolving primers (HARPs)--a modified technique of sequence-based typing (SBT).
OBJECTIVE
The aim was to evaluate the use of combination of SBT (sequence based typing) and HARP (heterozygous ambiguity resolving primer) in HLA typing to acquire high resolution typing results.


METHODS
167 DNA samples were analyzed by SBT. The web site HARPs Finder provided by Conexio Genomics, the developer of HARPs (http://www.harpsfinder.conexio-genomics.com/index.html) was then used to search for appropriate HARPs.


RESULTS
HARPs can resolve 95% of ambiguities for locus A; 86% for B and 60% for DRB1 locus. However, there are still limitations. Practically PCR products of un-separated alleles are used as templates for sequencing by HARP; sometimes, it is still impossible to get unambiguous typing.


CONCLUSIONS
We outlined the advantages and disadvantages of SBT/HARP. A list of HARPs for choice to resolve ambiguity of SBT in Taiwanese population is concluded.
Department of Pathology, National Defense Medical Center, Division of Clinical Pathology, Tri-Service General Hospital, Taipei, Taiwan, ROC.
Cherng-Lih
CL
Perng
Lei-Fa
LF
Chang
Wen-Chun
WC
Chien
Tsung D
TD
Lee
Jin-Biou
JB
Chang
D001483:Base Sequence; D017931:DNA Primers / Q000235:genetics*; D005787:Gene Frequency; D005805:Genes, MHC Class I; D005802:Genes, MHC Class II; D006580:Genetic Carrier Screening; D060005:Genotyping Techniques; D006648:Histocompatibility / Q000235:genetics; D006650:Histocompatibility Testing; D006801:Humans; D008969:Molecular Sequence Data; D017422:Sequence Analysis, DNA
D017931:DNA Primers