The development of cytogenetics and molecular genetics suggests a greater than expected importance of chromosomal, somatic and germ-line mosaicism. Mosaicism may cause varying expressivity of inherited diseases, aggregation of disorders regarded as "new mutations" in ostensibly healthy families, and neoplasia. Detection of latent parental mosaicism may enhance the prevention of abnormal offsprings. In clinical genetics this difficult problem may be solved from two approaches: 1. More thorough cytogenetic investigation of parents of children with chromosome aberrations. 2. Seeking for mild features of congenital disorders. The authors provide examples for these two possibilities from their own findings. Their family investigations suggest that an out-of-phase centromere separation may result in aneuploidy of the offspring even if it occurs in mosaic form in a part of the cells. At the same time, detailed investigation and anthropometric measurements of the parents of 28 children with multiple malformation syndromes revealed characteristic signs in at least one of the parents in 8 families. Among other factors also parental mosaicism should be taken into account, which should be considered in genetic counseling.
|Number of pages||5|
|Publication status||Published - aug. 19 1990|
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