Objective: To explore the genetic basis for a juvenile with maturity-onset diabetes of the young type 12(MODY12).
Methods: High-throughput sequencing was carried out to screen for the variants. Candidate variant was verified by Sanger sequencing. Pathogenity of the variant was predicted by searching the genetic databases and analysis by using bioinformatic software.
Results: Genetic testing indicated that the patient and his mother have both carried a heterozygous c.3976G>A variant (p.Glu1326Lys) in exon 32 of the ABCC8 gene. Prediction of the protein structure suggested the variant to be deleterious. Based on the guidelines of the American College of Medical Genetics and Genomics, the variant was predicted to be uncertain significance.
Conclusion: Whether the c.3976G>A variant of the ABCC8 gene is the cause of the disease in this patient or not depends on the functional studies and more case data. Above finding has enriched the spectrum of ABCC8 gene variants.