We have verified a lack of clinical response for both glycemic control and neurological features in an infant with permanent neonatal diabetes mellitus and DEND syndrome due to a V59A mutation in the KCNJ11 gene.
Permanent neonatal diabetes mellitus (PNDM) in European population has an incidence of at least 1 in 260 000 live births and is most commonly due to mutations in KCNJ11 and ABCC8.
Recessive EIF2AK3 gene mutations were the commonest cause of PNDM in the Arab cohort (22.7%) followed by INS (12.5%), and KCNJ11 and GCK (5.7% each), whereas K(ATP) channel mutations were the commonest cause (29.9%) in the British cohort.
Heterozygous mutations in ABCC8, KCNJ11, and INS genes account for around half of cases of PNDM; mutations in 10 further genes account for a further 10%, and the remaining 40% of cases are currently without a molecular genetic diagnosis.
Recessive EIF2AK3 gene mutations were the commonest cause of PNDM in the Arab cohort (22.7%) followed by INS (12.5%), and KCNJ11 and GCK (5.7% each), whereas K(ATP) channel mutations were the commonest cause (29.9%) in the British cohort.
Here, we defined a new variant of a known mutation, INS Exon 1-3 homozygous deletion, in two siblings diagnosed with permanent neonatal diabetes mellitus.
Although PNDM is a rare phenomenon (one case in about 200,000 live births), this discovery has had a large impact on clinical practice as most carriers of KCNJ11 and ABCC8 gene mutations have been switched from insulin to oral sulphonylureas with an improvement in glycemic control.
In the present study, we sequenced the KCNJ11 gene in a Chinese boy diagnosed with permanent neonatal diabetes mellitus (PNDM) and also in his parents.
Disruption of a novel Kruppel-like transcription factor p300-regulated pathway for insulin biosynthesis revealed by studies of the c.-331 INS mutation found in neonatal diabetes mellitus.
In summary, the switch from insulin therapy to SU treatment in PNDM related to KCNJ11 mutations was found to be an efficient and safe therapeutic method over a period of 34-month median follow-up.