Mutation spectrum and birth prevalence of inborn errors of metabolism among emiratis : a study from Tawam Hospital Metabolic Center, united Arab Emirates

الملخص EN

Objectives: This study aimed to determine the mutation spectrum and prevalence of inborn errors of metabolism (IEM) among Emiratis.

Methods: The reported mutation spectrum included all patients who were diagnosed with IEM (excluding those with lysosomal storage diseases [LSD]) at Tawam Hospital Metabolic Center in Abu Dhabi, United Arab Emirates, between January 1995 and May 2013.

Disease prevalence (per 100,000 live births) was estimated from data available for 1995–2011.

Results: In 189 patients, 57 distinct IEM were diagnosed, of which 20 (35%) entities were previously reported LSD (65 patients with 39 mutations), with a birth prevalence of 26.87/100,000.

This study investigated the remaining 37 (65%) patients with other IEM (124 patients with 62 mutations).

Mutation analysis was performed on 108 (87%) of the 124 patients.

Five patients with biotinidase deficiency had compound heterozygous mutations, and two siblings with lysinuric protein intolerance had two homozygous mutations.

The remaining 103 (95%) patients had homozygous mutations.

As of this study, 29 (47%) of the mutations have been reported only in Emiratis.

Two mutations were found in three tribes (biotinidase deficiency [BTD, c.1330G>C] and phenylketonuria [PAH, c.168+5G>C]).

Two mutations were found in two tribes (isovaleric aciduria [IVD, c.1184G>A] and propionic aciduria [PCCB, c.990dupT]).

The remaining 58 (94%) mutations were each found in individual tribes.

The prevalence was 48.37/100,000.

The most prevalent diseases (2.2–4.9/100,000) were biotinidase deficiency; tyrosinemia type 1; phenylketonuria; propionic aciduria; glutaric aciduria type 1; glycogen storage disease type Ia, and mitochondrial deoxyribonucleic acid depletion.

Conclusion: The IEM birth prevalence (LSD and non-LSD) was 75.24/100,000.

These results justify implementing prevention programmes that incorporate genetic counselling and screening