lost aneusomic chromosomal segment [GENO_0000345]

lost aneusomic chromosomal segment

ID: GENO_0000345

A deletion of a terminal portion of a chromosome resulting from an unbalanced translocation to another chromosome.

This is not a deletion in the sense defined by the Sequence Ontology in that it is not the result of an 'excision' of nucleotides, but an unbalanced translocation event. The allelic complement that results is comprised of the terminus or junction represented by this lost chromosomal segment, and the remaining normal segment in the homologous chromosome. The lost aneusommic chromosomal segment is typically accommpanied by a gained aneusomic chromosomal segment from another chromosome. Loss of translocated chromosomal parts can confer a monosomic condition to a region of the chromsome. This results in a 'variant single locus complement' - in virtue of an abnormal number of features at a particular locus, rather than abnormal sequence within the locus.