Heteromorphism 18ph+ : with or without reproductive consequences ?

• Published in: Annales de génétique Vol. 44; no. 3; pp. 139 - 142
• Main Authors: Tabet, A.C., Dupont, J.M., Lebbar, A., Couturier-Turpin, M.H., Feldmann, G., Rabineau, D.
• Format: Journal Article
• Language: English
• Published: Paris Elsevier SAS 01.07.2001; Société d'édition de l'association d'enseignement médical des hôpitaux de Paris
• Subjects: 18ph+ variant; Amniotic Fluid - metabolism; Biological and medical sciences; Chromosome Aberrations; Chromosome Banding; Chromosomes, Human, Pair 18; Diseases of mother, fetus and pregnancy; Female; genetic counselling; Gynecology. Andrology. Obstetrics; Humans; Hydrocephalus - genetics; Intellectual Disability - genetics; Karyotyping; Lymphangioma, Cystic - genetics; Medical sciences; Pregnancy; Pregnancy. Fetus. Placenta; Prenatal Diagnosis; PRINS technique; genetic counselling; 18ph+ variant; PRINS technique; Human; Relapse; Prognosis; Pregnancy disorders; In situ; Variations; Developmental disorder; Recurrent; Mental retardation; Abortion; Mechanism; Case study; Variant; Chromosome E18; Heterochromatin; Intellectual deficiency; Diagnosis; Technique; Child; Bibliographic review
• ISSN: 0003-3995
• DOI: 10.1016/S0003-3995(01)01079-6

Heteromorphism or chromosomal variants are usually attributed to structural variations in constitutive heterochromatin. In the case of chromosome 18, 25 cases of 18ph+ have been reported to date. Using the Primed In Situ Labelling technique (PRINS) to study 2 new cases of 18ph+, we have been able to confirm their molecular nature and assuming a mechanism of formation. Although such chromosomal variants are usually thought to have no adverse clinical consequence, a review of the literature shows that many cases were diagnosed because of recurrent abortion, malformed or mentally retarded children suggesting the possible relationship between 18ph+ and such clinical outcomes.