The detection of genetic polymorphism has become increasingly importan
t in forensic science as well as in medical genetics. In this report,
we describe a systematic flow chart system for HLA-DQA1 genotyping by
an improved PCR-RFLP (polymerase chain reaction-restriction fragment l
ength polymorphism) method coupled with the PRSM (PCR-mediated restric
tion site modification) method. This flow chart typing system can easi
ly discriminate between a total of eight reported DQA1 alleles commonl
y found in Chinese. We have applied this flow chart typing system in a
forensic case as well as in the determination of the frequencies of t
he eight DQA1 alleles in 121 unrelated Taiwan Chinese subjects. Our re
sults show that the flow chart DQA1 genotyping is a simple, fast, and
accurate system which, in the future, may be considered as an alternat
ive method for routine individual identification in forensic casework,
and for paternity testing and tissue typing in medical genetics.