Clinical and Oral Manifestations in a Patient with Lenz-Majewski Syndrome: A Rare Case Report

Lenz-Majewski Syndrome (LMS) is a rare multisystem genetic disorder characterized by intellectual disability, cutis laxa, craniofacial abnormalities, and distinct dental features. It is caused by gain-of-function mutations in the Phosphatidylserine Synthase 1 (PTDSS1) gene, which plays a key role in phospholipid biosynthesis. Among the craniofacial and dental manifestations, a progeroid facial appearance with prognathism, midface hypoplasia, large auricles, enamel dysplasia, delayed tooth eruption, and malocclusion are commonly observed. Due to the rarity and phenotypic variability of LMS, individual case reports remain essential for expanding the clinical and molecular understanding of the syndrome. We report a 13-year-old male diagnosed with Lenz-Majewski Syndrome (LMS) through whole exome sequencing, which identified a heterozygous de novo PTDSS1 variant (c.284G > A; p.R95Q), not previously documented in LMS cases. Clinical evaluation revealed moderate intellectual disability, cutis laxa, a progeroid facial appearance, and pronounced prognathism. Intraoral and radiographic examinations demonstrated enamel hypoplasia, taurodontism, delayed eruption of permanent teeth, a horizontally positioned upper lateral incisor, and a large follicular cyst in the maxilla. Orthodontic intervention using Hawley appliances was employed to stimulate the oral mucosa and support the eruption of delayed permanent teeth. This case expands the phenotypic and genotypic understanding of LMS and documents novel dental findings—particularly taurodontism—in association with a previously unreported PTDSS1 variant. It underscores the importance of early dental assessment and multidisciplinary care in managing LMS. Recognizing oral manifestations can facilitate timely diagnosis and personalized treatment strategies, contributing to improved quality of life in affected individuals.