Extracellular matrix protein 1 gene (ECM1) mutations in nine Iranian families with lipoid proteinosis

Lipoid proteinosis (LP) is an autosomal recessive disease. Clinical characteristics of this disease are hoarse voice, scarring of the skin, brain calcifications, and eyelid papules (moniliform blepharosis). Mutations in the ECM1 gene on 1q21.2 are responsible for this disease. This study was conducted to investigate the mutation spectrum of ECM1 gene in nine Iranian families having at least one LP patient diagnosed clinically.

The entire ECM1 gene was screened using PCR and direct sequencing in nine Iranian families with 12 suspected LP patients who were referred to the clinic, along with their parents and siblings. Thirty healthy individuals were included as controls.

In only one patient a homozygous G>A transition at nucleotide c.806 in exon 7 was detected. A G>A substitution at nucleotide 1243 in exon 8 that changes glycine (GGT) to serine (AGT) was observed in most of our patients. Furthermore, in one patient there was a change in the sequence of intron 8, the A>T transition in nucleotide 4307. In addition, in two cases (one patient and one healthy mother with affected child) there was a C (4249) deletion in intron 8.

Our results indicate that although mutation in ECM1gene is responsible for lipoid proteinosis, it is likely that this is not the only gene causing this disease and probably other genes may be involved in the pathogenesis of the LP disease.