A case report of a novel 22 bp duplication within exon 1 of the UGT1A1 in a Sudanese infant with Crigler-Najjar syndrome type I

• Published in: BMC gastroenterology Vol. 20; no. 1; pp. 62 - 4
• Main Authors: Valmiki, Sailaja, Mandapati, Kiran Kumar, Miriyala, Leela Krishna Vamsee, Kelgeri, Chayarani Chandrashekhar, Rela, Mohamed, Shanmugam, Naresh P, Vegulada, Durga Rao
• Format: Journal Article
• Language: English
• Published: England BioMed Central Ltd 06.03.2020; BioMed Central; BMC
• Subjects: Autosomal recessive; Bilirubin; Care and treatment; Case Report; Case reports; Case studies; Codons; Consanguinity; Crigler-Najjar syndrome; Crigler-Najjar Syndrome - genetics; Crigler-Najjar Syndrome - surgery; Diagnosis; Enzymes; Exons; Female; Gastroenterology; Gene Duplication; Genes; Genomics; Glucuronosyltransferase - genetics; Humans; Infant; Kernicterus; Light therapy; Liver; Liver transplant; Liver Transplantation; Liver transplants; Mutation; Novels; Organ transplantation; Parents & parenting; Pathogenesis; Pedigree; Phototherapy; Polymorphism; Sudan; Transplants & implants; UGT1A1; Sudan; India; Crigler-Najjar syndrome; Liver transplant; Autosomal recessive; Bilirubin; Mutation; UGT1A1
• ISSN: 1471-230X; 1471-230X
• DOI: 10.1186/s12876-020-01192-4

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. 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. 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.