Multiplex allele-specific PCR assay for differential diagnosis of Hb S, Hb D-Punjab and Hb Tak.
BACKGROUND
Apart from hemoglobin (Hb) E, Hb D-Punjab [beta121(GH4)Glu-Gln] and Hb Tak [beta147Term-Thr] are the two most common beta-chain variants among the Asian population. These two Hb variants have similar alkaline electrophoretic mobilities and HPLC profiles as those of the Hb S [beta6(A3)Glu-Val]. Differential diagnosis of these clinically relevant hemoglobinopathies is therefore problematic. Direct detection of the beta-globin gene mutations would be another diagnostic alternative.


METHODS
A simultaneous DNA diagnosis of the three Hb variants was developed based on the multiplex allele-specific polymerase chain reaction (PCR) approach. The method was validated on 10 carriers of Hb D-Punjab, 5 carriers of Hb Tak, 2 carriers of Hb S and 50 normal individuals of Thai origin.


RESULTS
The three abnormal Hbs could be correctly diagnosed with the simultaneous PCR approach, and a complete concordance with results using other established methods was obtained.


CONCLUSIONS
The multiplex allele-specific PCR approach developed should prove useful in complementing routine Hb analysis for differential diagnosis of these three common Hb variants and should facilitate a program of hemoglobinopathy screening in the region.
Sanchaisuriya
Kanokwan
K
Department of Clinical Microscopy, Faculty of Associated Medical Sciences, Khon Kaen University, Thailand.
Chunpanich
Sunisa
S
Fucharoen
Goonnapa
G
Fucharoen
Supan
S
D000483:Alleles; D002851:Chromatography, High Pressure Liquid; D003937:Diagnosis, Differential; D005260:Female; D005820:Genetic Testing; D006451:Hemoglobin, Sickle / Q000235:genetics*; D006453:Hemoglobinopathies / Q000097:blood / Q000175:diagnosis* / Q000235:genetics*; D006455:Hemoglobins, Abnormal / Q000235:genetics*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008297:Male; D016133:Polymerase Chain Reaction; D017085:alpha-Thalassemia / Q000097:blood
D006451:Hemoglobin, Sickle; D006455:Hemoglobins, Abnormal; C111400:hemoglobin Tak; C026237:hemoglobin D Punjab