Description
In Press In humans, bilirubin levels are influenced by different
factors. This study aims to evaluate the influence of several nongenetic
factors (hematologic data, smoking status, alcohol intake, fasting time,
physical activity, oral contraceptive therapy and caloric intake) and the
genetic contribution of UGT1A1 polymorphisms for the bilirubin levels,
in a cohort of young women. Hematologic data, bilirubin and
screening of TA duplication in the TATA box region of the UGT1A1
gene were performed in 146 young white women. Body mass index
(BMI) and body fat were determined, and a questionnaire about fasting
time, smoking habits, oral contraceptive therapy, caloric intake and
physical activity was performed. Participants were divided into 3
groups according to the tertiles of bilirubin levels. Subjects from the
second and third tertile had significant increases in hemoglobin (Hb)
concentration, hematocrit, mean cell Hb and mean cell Hb concentration
compared with those in the first tertile. Red blood cell count was
significantly increased in subjects in the third tertile. A significant
increased frequency was found for the c.-41_-40dupTA allele in homozygosity
for both second and third tertiles. Multiple linear regression
analysis showed that the c.-41_-40dupTA allele, Hb, BMI and fasting
hours were independent variables associated with bilirubin serum
levels. Hb concentration, fasting time and BMI were identified as
nongenetic causes, together with the genetic UGT1A1 polymorphisms,
as the main factors associated with variations in bilirubin levels in a
healthy female population.
; Costa, Elísio 
