a novel deletion mutation in aspm gene in an iranian family with autosomal recessive primary microcephaly

how to cite this article: akbarizar e, ebrahimpour m, akbari s, arzhanghi s, abedini ss, najmabadi h, kahrizi k. a novel deletion mutation in aspm gene in an iranian family with autosomal recessive primary microcephaly. iran j child neurol.  2013 spring;7(2):23-30.   objective autosomal recessive primary microcephaly (mcph) is a neurodevelopmental and genetically heterogeneous disorder with decreased head circumference due to the abnormality in fetal brain growth. to date, nine loci and nine genes responsible for the situation have been identified. mutations in the aspm gene (mcph5) is the most common cause of mcph. the aspm gene with 28 exons is essential for normal mitotic spindle function in embryonic neuroblasts. materials & methods we have ascertained twenty-two consanguineous families with intellectual disability and different ethnic backgrounds from iran. ten out of twenty-two families showed primary microcephaly in clinical examination. we investigated mcph5 locus using homozygosity mapping by microsatellite marker. result sequence analysis of exon 8 revealed a deletion of nucleotide (t) in donor site of splicing site of aspm in one family. the remaining nine families were not linked to any of the known loci. more investigation will be needed to detect the causative defect in these families. conlusion we detected a novel mutation in the donor splicing site of exon 8 of the aspm gene. this deletion mutation can alter the aspm transcript leading to functional impairment of the gene product.   references 1. pattison l, crow yj, deeble vj, jackson ap, jafri h, rashid y, et al. a fifth locus for primary autosomal recessive microcephaly maps to chromosome 1q31. am j hum genet 2000;67(6):1578-80. 2. darvish h, esmaeeli-nieh s, monajemi g, mohseni m, ghasemi-firouzabadi s, abedini s, et al. a clinical and molecular genetic study of 112 iranian families with primary microcephaly. journal of medical genetics 2010;47(12):823-8. 3. tolmie jl, m m, jb s, d d, jm 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