AIM： To identify the variants in U rase 1 （UGT1A1） gene in Gilbert＇s syndrome （GS） and to estimate the association between homozygosity for TA insertion and GS in India, as well as the frequency of TA insertion ...AIM： To identify the variants in U rase 1 （UGT1A1） gene in Gilbert＇s syndrome （GS） and to estimate the association between homozygosity for TA insertion and GS in India, as well as the frequency of TA insertion and its impact among normal controls in India. METHODS： Ninety-five GS cases and 95 normal controls were selected. Liver function and other tests were done. The promoter and all 5 exons of UGT1A1 gene were resequenced. Functional assessment of a novel trinucleotide insertion was done by in silico analysis and by estimating UGT1A1 promoter activity carried out by ludferase reporter assay of appropriate constructs in Hep G2 cell line. RESULTS： Among the GS patients, 80% were homozygous for the TA insertion, which was several-fold higher than reports from other ethnic groups. The mean UCB level was elevated among individuals with only one copy of this insertion, which was not significantly different from those with two copies. Many new DNA variants in UGT1A1 gene were discovered, including a trinucleotide （CAT） insertion in the promoter found in a subset （10%） of GS patients, but not among normal controls. In-silico analysis showed marked changes in the DNA-folding of the promoter and functional analysis showed a 20-fold reduction in transcription efficiency of UGT1A1 gene resulting from this insertion, thereby significantly elevating the UCB level. CONCLUSION： The genetic epidemiology of GS is variable across ethnic interactions among UGT1A1 groups and the epistatic promoter variants modulate bilirubin glucuronidation.展开更多
This study attempts to discuss the correlation between UGT1A1＊28 as uridine diphosphate glucuronosyltransferase gene promoter and coding region Gly71 Arg gene polymorphism with neonatal hyperbilirubinemia of neonates...This study attempts to discuss the correlation between UGT1A1＊28 as uridine diphosphate glucuronosyltransferase gene promoter and coding region Gly71 Arg gene polymorphism with neonatal hyperbilirubinemia of neonates in Wuhan. A total of 168 neonates were divided into the hyperbilirubinemia group（case group, n=108） and healthy neonates group（control group, n=60）. Their DNA was obtained through blood extraction. The gene exon mutation of UGT1A1 was detected by Sanger sequencing, which revealed the relationship between UGT1A1＊28 and Gly71 Arg polymorphism with neonatal hyperbilirubinemia of neonates. The results showed that：（1） The frequency of UGT1A1＊28 allele mutation in the case group and the control group was 9.3% and 10% respectively, with the difference being not significant between the two groups（P〉0.05）.（2） The frequency of Gly71 Arg allele mutation in the case group and the control group was 35.1% and 21.7% respectively, with the difference being significant between the two groups（P〈0.01）.（3） The serum bilirubin level of Gly71 Arg mutant homozygous and heterozygous subgroups（n=66） in the case group was 302.7±31.4 μmol/L, which was significantly higher than 267.3±28.5 μmol/L of the wild subgroup（n=42）（P〈0.01）. It was suggested that the occurrence of neonatal hyperbilirubinemia of neonates in Wuhan was not associated with UGT1A1＊28 gene polymorphism, but closely with the Gly71 Arg gene polymorphism. Meanwhile, the Arg allele mutation was related to the degree of jaundice.展开更多
基金Supported by grants from the Department of Biotechnology, Government of India (to PPM) and the Department of Science & Technology, Government of West Bengal (to AC)
文摘AIM： To identify the variants in U rase 1 （UGT1A1） gene in Gilbert＇s syndrome （GS） and to estimate the association between homozygosity for TA insertion and GS in India, as well as the frequency of TA insertion and its impact among normal controls in India. METHODS： Ninety-five GS cases and 95 normal controls were selected. Liver function and other tests were done. The promoter and all 5 exons of UGT1A1 gene were resequenced. Functional assessment of a novel trinucleotide insertion was done by in silico analysis and by estimating UGT1A1 promoter activity carried out by ludferase reporter assay of appropriate constructs in Hep G2 cell line. RESULTS： Among the GS patients, 80% were homozygous for the TA insertion, which was several-fold higher than reports from other ethnic groups. The mean UCB level was elevated among individuals with only one copy of this insertion, which was not significantly different from those with two copies. Many new DNA variants in UGT1A1 gene were discovered, including a trinucleotide （CAT） insertion in the promoter found in a subset （10%） of GS patients, but not among normal controls. In-silico analysis showed marked changes in the DNA-folding of the promoter and functional analysis showed a 20-fold reduction in transcription efficiency of UGT1A1 gene resulting from this insertion, thereby significantly elevating the UCB level. CONCLUSION： The genetic epidemiology of GS is variable across ethnic interactions among UGT1A1 groups and the epistatic promoter variants modulate bilirubin glucuronidation.
基金supported by the National Natural Science Foundation of China(No.81370099)
文摘This study attempts to discuss the correlation between UGT1A1＊28 as uridine diphosphate glucuronosyltransferase gene promoter and coding region Gly71 Arg gene polymorphism with neonatal hyperbilirubinemia of neonates in Wuhan. A total of 168 neonates were divided into the hyperbilirubinemia group（case group, n=108） and healthy neonates group（control group, n=60）. Their DNA was obtained through blood extraction. The gene exon mutation of UGT1A1 was detected by Sanger sequencing, which revealed the relationship between UGT1A1＊28 and Gly71 Arg polymorphism with neonatal hyperbilirubinemia of neonates. The results showed that：（1） The frequency of UGT1A1＊28 allele mutation in the case group and the control group was 9.3% and 10% respectively, with the difference being not significant between the two groups（P〉0.05）.（2） The frequency of Gly71 Arg allele mutation in the case group and the control group was 35.1% and 21.7% respectively, with the difference being significant between the two groups（P〈0.01）.（3） The serum bilirubin level of Gly71 Arg mutant homozygous and heterozygous subgroups（n=66） in the case group was 302.7±31.4 μmol/L, which was significantly higher than 267.3±28.5 μmol/L of the wild subgroup（n=42）（P〈0.01）. It was suggested that the occurrence of neonatal hyperbilirubinemia of neonates in Wuhan was not associated with UGT1A1＊28 gene polymorphism, but closely with the Gly71 Arg gene polymorphism. Meanwhile, the Arg allele mutation was related to the degree of jaundice.
