Introduction Monogenic diabetes is a type of diabetes resulting from mutations of a single gene that may be spontaneous de novo or autosomal dominant or recessive. Reported incidence is 1–4% and confirmed by molecular genetic testing. Transient neonatal diabetes is usually diagnosed within the first week of life and resolves around 12 weeks. Permanent neonatal diabetes should be considered in all children presenting with diabetes in first month of age, and do not resolve. Genetic diagnosis may have major effects on treatment.

Objective To determine the genetic mutation pattern of suspected cases of monogenic diabetes in patients referred to Makassed Hospital in Jerusalem.

Methods Molecular detection has been done for those infants who were fulfilling the following criterion:

Infants with diabetes both transient (TNDM) and permanent neonatal diabetes (PNDM), Infants with diabetes diagnosed between 6 and 12 months of age and negative antibodies, Infants with diabetes associated with extra pancreatic features, Infants with diabetes presenting before 6 months of age as type 1 diabetes.

Results Patients were evaluated at Makassed Hospital, underwent genetic testing and revealed 10 novel mutations, 3 with previously described mutations and another 2patients without final genetic diagnosis.

Conclusion Monogenic diabetes is not very uncommon, higher rate of consanguinity predicts higher risk and is often misdiagnosed as type 1 or type 2 diabetes.

Diabetes diagnosed before 6 months of age will be monogenic diabetes and the underlying gene mutations can be identified in most of the cases, guiding the most appropriate management for patients.

This will enable genetic counselling, correcting the diagnosis of other family member & explain other associated features; predict the clinical course of the disease.