| imprinting | 1. <genetics> A remarkable genetic phenomenon. The gist is that gene expression depends on the sex of the transmitting parent. There is, for example, increased severity of neurofibromatosis when the gene for it came from the mother. 2. <psychology> A particular kind of learning characterised by occurrence in very early life, rapidity of acquisition, and relative insusceptibility to forgetting or extinction. Imprinted behaviour includes most (or all) behaviour commonly called instinctive, but imprinting is used purely descriptively. (04 Jul 1999) |
|---|
| genomic imprinting | <genetics, molecular biology> Parent specific expression or repression of genes or chromosomes in offspring. There are an increasing number of recognised chromosomal imprinting events in pathological conditions: for example preferential transmission of paternal or maternal predisposition to diabetes or atopy, preferential retention of paternal alleles in rhabdomyosarcoma, osteosarcoma, retinoblastoma and Wilm's tumour, preferential translocation to the paternal chromosome 9 of a portion of maternal chromosome 22 to form the Philadelphia chromosome of chronic myeloid leukaemia. (18 Nov 1997) |
|---|