Deletion (genetics)

Deletions that do not occur in multiples of three bases can cause a frameshift by changing the 3-nucleotide protein reading frame of the genetic sequence.

[9] Deletion of part of the short arm of chromosome 5 results in Cri du chat syndrome.

[11] Recent work suggests that some deletions of highly conserved sequences (CONDELs) may be responsible for the evolutionary differences present among closely related species.

[13] The introduction of molecular techniques in conjunction with classical cytogenetic methods has in recent years greatly improved the diagnostic potential for chromosomal abnormalities.

In particular, microarray-comparative genomic hybridization (CGH) based on the use of BAC clones promises a sensitive strategy for the detection of DNA copy-number changes on a genome-wide scale.

[14] Other computation methods were selected to discover DNA sequencing deletion errors such as end-sequence profiling.

Deletion on a chromosome
Three chromosomal abnormalities with ISCN nomenclature, with increasing complexity: (A) A tumour karyotype in a male with loss of the Y chromosome, (B) Prader–Willi Syndrome i.e. deletion in the 15q11-q12 region and (C) an arbitrary karyotype that involves a variety of autosomal and allosomal abnormalities. [ 6 ]
Human karyotype with annotated bands and sub-bands as used for the nomenclature of chromosome abnormalities. It shows dark and white regions as seen on G banding . Each row is vertically aligned at centromere level. It shows 22 homologous autosomal chromosome pairs, both the female (XX) and male (XY) versions of the two sex chromosomes , as well as the mitochondrial genome (at bottom left).
Further information: Karyotype