A case report of prenatally diagnosed tetrasomy 18p

Tetrasomy 18p, one of the most commonly observed isochromosomes, consists of two copies of the p arms on chromosome 18[i(18p)]. It is known as a de novo occurrence of non-disjunction or centromeric mis-division during meiosis II in the vast majority of cases. It has a prevalence of 1/140,000-180,000 live births and affects both genders equally. A 28-year-old woman was referred at 33+2 weeks gestation to rule out fetal congenital heart disease. Her prenatal ultrasonography showed intrauterine growth retardation, cardiomegaly, and imperforate anus. Doppler ultrasonographic finding showed fetal anemia. Tetrasomy 18p was confirmed by conventional karyotyping and fluorescence in situ hybridization. Because of its very low prevalence rate, only several cases of tetrasomy 18p has been reported worldwide and it has not yet been reported in Korea before. Therefore, we report a case of prenatally diagnosed tetrasomy 18p.

[1]  V. Plaiasu,et al.  A rare chromosomal disorder - isochromosome 18p syndrome. , 2011, Maedica.

[2]  B. Uerpairojkit,et al.  Causes and consequences of 93 fetuses with cardiomegaly in a tertiary center in Thailand , 2011, Archives of Gynecology and Obstetrics.

[3]  E. Roeder,et al.  Tetrasomy 18p: Report of the molecular and clinical findings of 43 individuals , 2010, American journal of medical genetics. Part A.

[4]  L. Figuera,et al.  The variable phenotype in tetrasomy 18p syndrome. A propos of a subtle dysmorphic case. , 2010, Genetic counseling.

[5]  N. Ramachandra,et al.  De novo isochromosome 18p in a female dysmorphic child , 2010, Journal of Applied Genetics.

[6]  A. Caglayan,et al.  A case with a rare chromosomal abnormality: isochromosome 18p. , 2010, Genetic counseling.

[7]  I. Chudoba,et al.  Constitutional tetrasomy 18p. , 2006, Indian pediatrics.

[8]  S. Patil,et al.  Behavioral management of a long‐term survivor with tetrasomy 18p , 2006, American journal of medical genetics. Part A.

[9]  W. Robinson,et al.  Grandmaternal origin of an isochromosome 18p present in two maternal half-sisters. , 2001, American journal of medical genetics.

[10]  R. Naeem,et al.  Prenatal diagnosis and clinical features of an individual with tetrasomy 18p and trisomy 18q mosaicism. , 1998, Journal of perinatology : official journal of the California Perinatal Association.

[11]  L. Brečević,et al.  Isochromosome 18p Results from Maternal Meiosis II Nondisjunction , 1996, European journal of human genetics : EJHG.

[12]  J. Cantú,et al.  Tetrasomy 18p: a distinctive syndrome. , 1984, Annales de Genetique.