The variable phenotype in tetrasomy 18p syndrome. A propos of a subtle dysmorphic case

• Published in: Genetic counseling Vol. 21; no. 3; pp. 277 - 283
• Main Authors: Brambila Tapia, A J, Figuera, L, Vázquez Cárdenas, N A, Ramírez Torres, V, Vázquez Velázquez, A I, García Contreras, C, Ramírez Dueñas, M L
• Format: Journal Article
• Language: English
• Published: Switzerland Éditions Médecine et Hygiène 01.01.2010
• Subjects: Aneuploidy; Child, Preschool; Chromosomes, Human, Pair 18 - genetics; Craniofacial Abnormalities - genetics; Developmental Disabilities - genetics; Female; Humans; Intellectual Disability - genetics; Isochromosomes - genetics; Karyotyping; Male; Muscle Spasticity - genetics; Phenotype; Syndrome
• ISSN: 1015-8146

The variable phenotype in tetrasomy 18p syndrome. Apropos of a subtle dysmorphic case: Tetrasomy 18 is a rare chromosomal syndrome. Its frequency is 1/40,000 newborns and more than 40 cases have been reported. In this paper we report a 25-month-old female patient referred for chromosome examination essentially because of delayed psychomotor development. The physical examination showed: microcephaly, mild generalized spasticity, arched eyebrows, horizontal palpebral fissures with unilateral convergent strabismus, bilateral epicanthic folds, small nose, well placed ears, oral cavity with high arched palate and upper vestibular frenula, tented mouth with slightly everted upper lip, hands with normal palmar creases and long fingers. All the blood tests were normal, while the magnetic resonance imaging reported mild demyelination and polymicrogyria. The karyotype was 47,XX,+i(18)(p10).ish i(18)(plO)(D18Z1+) de novo.