2021 年 67 巻 6 号 p. 359-364
18q (–) syndrome is a deletion syndrome reported in 1964 by de Grouchy, in which part of the long arm of chromosome 18 is deleted. The incidence rate is said to be one in 40,000 people. 18q (–) syndrome has various phenotypes such as retardation of mental development, a drop in muscle tonus, short stature, hearing loss, limb abnormality, congenital heart disease, and cleft lip and palate. In this case, bilateral cleft lip and palate was observed at birth, and a suckling disorder was reported by the maternity department, so we visited the hospital. At first, cleft lip and palate, low-set ears and interocular dissection were observed, however no systemic abnormal findings were observed.