Bilirubin concentrations in thalassemia heterozygotes in university students.
OBJECTIVE
To investigate the difference of bilirubin concentrations between α- and β-thalassemia carriers and the role of variation status in the UDP-glucuronosyltransferase (UGT) 1A1 gene on such a difference.


METHODS
A total of 2713 university freshmen who attended a regular physical examination were enrolled in underwent screenings for thalassemias. Finally, 123 subjects whose mean corpuscular volume was ≤80 fL and who had no iron deficiency anemia were tested by PCR and PCR-restriction fragment length polymorphism (RFLP) for α- and β-thalassemias, respectively, and tested by PCR-RFLP for the five known variations of the UGT1A1 gene.


RESULTS
Among the 123 subjects, 76 and 47 were diagnosed with heterozygous α-thalassemia and with heterozygous β-thalassemia, respectively. Between the α- and β-thalassemia heterozygotes, variation status of the UGT1A1 gene was not statistically different (P = 0.898), while hemoglobin and bilirubin concentrations differed significantly (P = 0.005 and 0.001, respectively). Bilirubin concentrations were significantly higher among individuals with compound heterozygous variations/homozygous variation in the UGT1A1 gene than in those possessing the wild type and heterozygous variation (P < 0.001 for both α- and β-thalassemia heterozygotes). Compound heterozygous variations/homozygous variation in the UGT1A1 gene and anemia were the main causes of hyperbilirubinemia in α- and β-thalassemia heterozygotes, respectively.


CONCLUSIONS
The difference in bilirubin concentrations between α- and β-thalassemia heterozygotes may be attributable to more bilirubin being produced in β-thalassemia heterozygotes than in α-thalassemia heterozygotes, while variation status of the UGT1A1 gene affects bilirubin concentrations in both α- and β-thalassemia heterozygotes.
Department of Laboratory Medicine, Taipei District, Cathay General Hospital, Taipei, Taiwan. chsh.huang@msa.hinet.net
Yang-Yang
YY
Huang
May-Jen
MJ
Huang
Hai-Lung
HL
Wang
Cung-Cuan
CC
Chan
Ching-Shan
CS
Huang
D018798:Anemia, Iron-Deficiency / Q000097:blood; D001663:Bilirubin / Q000097:blood*; D005260:Female; D014453:Glucuronosyltransferase / Q000235:genetics; D006454:Hemoglobins / Q000378:metabolism; D006579:Heterozygote; D006801:Humans; D008297:Male; D008403:Mass Screening; D013334:Students; D013624:Taiwan / Q000453:epidemiology; D055815:Young Adult; D017085:alpha-Thalassemia / Q000097:blood* / Q000201:enzymology / Q000453:epidemiology / Q000235:genetics*; D017086:beta-Thalassemia / Q000097:blood* / Q000201:enzymology / Q000453:epidemiology / Q000235:genetics*; D000099148:UGT1A1 Enzyme
D001663:Bilirubin; D014453:Glucuronosyltransferase; D006454:Hemoglobins; D000099148:UGT1A1 Enzyme