I am reading a journal paper about the association between NCAM2 and autism, and I have come across the following:

We performed microarray analysis and identified a 1.6-Mb deletion of 21q21.1-q21.2, containing the NCAM2 gene but no other functional gene.

I am not sure what the '-q21.2' after '21q21.1' in '21q21.1-q21.2' means. Does it mean that the deletion goes between band 21.1 to 21.2 on the long arm of chromosome 21 (21q)? Any insights are appreciated.


Cytogenetic map notation uses the following form:


Where A is the chromosome number, p is the petit / short arm, q is the queue / long arm, B is the band, C is the sub-band, and D is the sub-sub-band.

So, 21q21.1-q21.2 designates a region on the long arm of chromosome 21, band 2, sub-band 1, between sub-sub-bands 1 and 2.

Source: NCBI Genetics Review (archived version)


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