Reyhaneh Kameli - Myelin Disorders Clinic, Pediatric Neurology Division, Children's Medical Center, Pediatrics Center of Excellence, Tehran University of Medical Sciences, Tehran, Iran
Mahmoud Reza Ashrafi - Myelin Disorders Clinic, Pediatric Neurology Division, Children's Medical Center, Pediatrics Center of Excellence, Tehran University of Medical Sciences, Tehran, Iran
Farveh Ehya - Department of Medical Biotechnology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
Farveh Ehya - Department of Medical Biotechnology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
Houman Alizadeh - Department of Pediatrics, Division of Pediatric Radiology, Children's Medical Center, Tehran University of Medical Sciences, Tehran, Iran
Sareh Hosseinpour - Myelin Disorders Clinic, Pediatric Neurology Division, Children's Medical Center, Pediatrics Center of Excellence, Tehran University of Medical Sciences, Tehran, Iran

RIN2 syndrome also known as MACS syndrome is a rare autosomal recessive connective tissue disorder caused by RIN2 mutations and is accompaniedby following clinical features: macrocephaly, coarsening of facial features, downward slanting palpebral fissures, Puffy droopy eyelids, full everted lips, softredundant skin especially in face, gum hypertrophy, irregular dentition, sparse scalp hair, skeletal problems, joint hypermobility and scoliosis. RIN2 gene encodesthe RAS and RAB interactor 2 and biallelic mutations in this gene cause cell trafficking dysfunction. Here we reported the eleventh patient of RIN2 syndrome in a4 yr-old boy, from Tehran, Iran as the youngest reported patient so far. Whole exome sequencing revealed a novel frameshift homozygous variant ofNM_001242581.1: c.2251dup; p.(Leu751Profs*9) in RIN2 gene. In addition to the previously reported symptoms for the RIN2 syndrome, white matterabnormalities in his brain MRI were noticed. Our findings expand the clinical spectrum of MACS syndrome due to mutation in RIN2 gene.

RIN2, MACS syndrome, Coarsening face, White matter abnormality, MRI