First report of neonatal-onset glutaric aciduria type II in the Iranian population caused by a novel deleterious ETFA variant.

BACKGROUND

Glutaric acidemia type II (GA2), also known as multiple acyl-CoA dehydrogenase deficiency (MADD), is a rare inherited error of amino acid and fatty acid metabolism. Its clinical manifestations can vary from severe events that threaten the life of a newborn to milder and late manifestations. Here, we examined an Iranian couple for pre-pregnancy counseling who had a history of the death of two children suspected of metabolic disorder.

METHODS

Whole exome sequencing (WES) was performed to determine possible pathogenic genes in the parents of two deceased neonates. Sanger sequencing was then used to confirm the variant found. Subsequently, the possible impact of the identified variant on the ETFA protein was evaluated using bioinformatics tools.

RESULTS

WES identified a novel heterozygous in-frame variant c.485_493del: p.E162_T164del in exon 6 of the ETFA gene, which co-segregated with the autosomal recessive GA2 disorder in the family studied. Sanger sequencing confirmed the variant found in the parents and their healthy family members and in silico approaches showed disease-causing nature of the identified mutation. Following the confirmation of the identified variant in the fetus, a legal abortion permit was issued, and the fetus was terminated with the parents' consent.

CONCLUSIONS

This is the first reported case of GA2 caused by a variant in the ETFA gene in Iran and shows the importance of genetic diagnosis and management of rare clinical manifestations and conditions that can help predict prognosis and provide more accurate diagnostic information for patients and families with GA2.