14.Ulusal Tıbbi Genetik Kongresi “Uluslararası Katılımlı”, Ankara, Turkey, 20 - 22 November 2020, pp.69
Acromesomelic Dysplasia Maroteaux type (AMDM) which belongs to the group of acromesomelic dysplasias is an extremely rare skeletal disorder described by severe shortening of the forelimbs and disproportionate short stature. AMDM is an autosomal recessive genetic disorder with a prevalence of 1/1,000,000. Clinical features of the syndrome are short broad fingers, square flat feet, and shortening of the long bones, radial bowing, dolichocephaly, frontal bossing, and normal facial appearance and intelligence This condition is caused by homozygous or compound heterozygous mutations in the natriuretic peptide receptor 2 (NPR2) gene, located on chromosome 9p13. NPR2 gene encodes natriuretic peptide receptor B (NPR-B) that plays a critical role in endochondral ossification, which is responsible for longitudinal growth in limbs and vertebrae. Here we reported two Turkish siblings presenting with severe dwarfism and atypic skeletal findings. Next Generation sequence analysis revealed a novel pathogenic variant in NPR2 (c. 661G>A, p. (Gly221Arg)) which was found to be homozygous in the siblings. Both siblings were identified with a novel missense NPR2 mutation and were diagnosed with AMDM. Their parents are carriers of the same variant.