The phenotype of neonatal diabetes with intestinal atresia and biliary agenesis clearly pointed to RFX6 as the causative gene; indeed, whole exome sequencing revealed a novel homozygous RFX6 mutation c.779A>C; p.Lys260Thr (K260T).
Mutations in the RFX6 gene were recently described to underlie a distinct autosomal recessive syndrome of neonatal diabetes comprising intestinal atresia and hepatobiliary abnormalities.