ABSTRACT
BACKGROUND: Crigler Najjar type 1 is a rare autosomal recessive condition caused by the absence of UDPGT enzyme due to mutations in the UGT1A1 gene. This enzyme is responsible for elimination of unconjugated bilirubin from the body by glucuronidation. Affected individuals are at risk for kernicterus and require lifelong phototherapy. Liver transplant is the only definitive treatment. CASE PRESENTATION: Here we report a case of a 6 month old Sudanese female infant with CN1 whose molecular analysis revealed a novel homozygous 22 base pair duplication (c.55_76dup) in the coding exon 1 of the UGT1A1 gene. This 22 bp duplication causes a frame shift leading to a premature stop codon. She underwent a successful liver transplant at 7 months of age and is doing well at 1 year follow-up. CONCLUSION: This study shows that molecular diagnosis helps in precise diagnosis of CN1 and in prognosis, prompt medical intervention and appropriate therapy. This particular 22 bp duplication within the coding region of UGT1A1 can be a founder mutation in the Sudanese population.
Subject(s)
Crigler-Najjar Syndrome/genetics , Gene Duplication , Glucuronosyltransferase/genetics , Consanguinity , Crigler-Najjar Syndrome/surgery , Exons , Female , Humans , Infant , Liver Transplantation , Pedigree , SudanABSTRACT
Asia harbors substantial cultural and linguistic diversity, but the geographic structure of genetic variation across the continent remains enigmatic. Here we report a large-scale survey of autosomal variation from a broad geographic sample of Asian human populations. Our results show that genetic ancestry is strongly correlated with linguistic affiliations as well as geography. Most populations show relatedness within ethnic/linguistic groups, despite prevalent gene flow among populations. More than 90% of East Asian (EA) haplotypes could be found in either Southeast Asian (SEA) or Central-South Asian (CSA) populations and show clinal structure with haplotype diversity decreasing from south to north. Furthermore, 50% of EA haplotypes were found in SEA only and 5% were found in CSA only, indicating that SEA was a major geographic source of EA populations.
Subject(s)
Asian People/genetics , Emigration and Immigration , Ethnicity/genetics , Haplotypes , Polymorphism, Single Nucleotide , Algorithms , Asia , Asian People/history , Bayes Theorem , Cluster Analysis , Emigration and Immigration/history , Ethnicity/history , Gene Flow , Genotype , Geography , History, Ancient , Humans , Language , Linguistics , Oligonucleotide Array Sequence Analysis , Phylogeny , Principal Component AnalysisABSTRACT
BACKGROUND: Quantitative variation in gene expression has been proposed to underlie phenotypic variation among human individuals. A facilitating step towards understanding the basis for gene expression variability is associating genome wide transcription patterns with potential cis modifiers of gene expression. DESCRIPTION: EXPOLDB, a novel Database, is a new effort addressing this need by providing information on gene expression levels variability across individuals, as well as the presence and features of potentially polymorphic (TG/CA)n repeats. EXPOLDB thus enables associating transcription levels with the presence and length of (TG/CA)n repeats. One of the unique features of this database is the display of expression data for 5 pairs of monozygotic twins, which allows identification of genes whose variability in expression, are influenced by non-genetic factors including environment. In addition to queries by gene name, EXPOLDB allows for queries by a pathway name. Users can also upload their list of HGNC (HUGO (The Human Genome Organisation) Gene Nomenclature Committee) symbols for interrogating expression patterns. The online application 'SimRep' can be used to find simple repeats in a given nucleotide sequence. To help illustrate primary applications, case examples of Housekeeping genes and the RUNX gene family, as well as one example of glycolytic pathway genes are provided. CONCLUSION: The uniqueness of EXPOLDB is in facilitating the association of genome wide transcription variations with the presence and type of polymorphic repeats while offering the feature for identifying genes whose expression variability are influenced by non genetic factors including environment. In addition, the database allows comprehensive querying including functional information on biochemical pathways of the human genes. EXPOLDB can be accessed at http://expoldb.igib.res.in/expol.
