GILBERT-SYNDROME ACCELERATES DEVELOPMENT OF NEONATAL JAUNDICE

Objective: Gilbert Syndrome (GS), associated with unconjugated hyperbi lirubinemia and decreased bilirubin UDP-glucuronosyltransferase activi ty, is usually diagnosed after puberty. The role of GS in neonatal jau ndice is unknown. This study tested the hypothesis that a recently ide ntified;ed molecular marker for GS (a TA insertion in the promoter of UGT1A, the gene encoding bilirubin UDP-glucuronosyltransferase) is ass ociated with neonatal jaundice. Study design: Transcutaneous jaundice index was measured shortly after birth and daily for the first week of life in 151 healthy infants. Genomic DNA was isolated from blood or b uccal brushings, and the UGT1A promoter was amplified by the polymeras e chain reaction to yield 90 (A[TA](6)TAA, normal) or 92 (A[TA](7)TAA, GS) base pair products. Statistical analysis used Kruskal-Wallis, Wil coxon, and Fisher's exact tests. Results: Nineteen (13%) subjects were homozygous for the A(TA)(7)TAA polymorphism associated with GS. The A (TA)(7)TAA homozygotes had a greater increase in jaundice index during the first 2 days of life than heterozygotes or A(TA)(6)TAA homozygote s. Conclusion: Although peak jaundice levels did not differ among grou ps, newborn infants with the molecular marker for GS have an accelerat ed increase in neonatal jaundice during the first 2 days of life.