Determine the effects of chromosome 18 gene deletions or duplications.
There are two sets of maps. The first set (Scientific Maps) are more scientifically oriented with gene dosage information for every gene on chromosome 18.
The second set is (Clinical Maps) are medically-oriented with information for only those few genes that have a clinical impact when deleted or duplicated.
The genes that are not included in this application have data showing that they do not play any role when deleted or duplicated. To date (2025), of the 263 genes on chromosome 18, only 18 genes have an unknown role when deleted and 99 have an unknown role when duplicated. At this point in time, not every characteristic of someone with a chromosome 18 condition can be explained by these data.
Scientific Maps
These data are displayed as custom tracks on the University of California Genome Browser. Every gene on chromosome 18 is depicted at its location on the chromosome and classified with regard to the likelihood of being dosage sensitive. There is one track for the effects of hemizygosity (gene deletion) and one for suprazygosity (gene duplication). By clicking on the gene in the browser track the user is taken to the details page with supporting data.
Clinical Maps
There are two types of clinical dosage maps. The first includes only those few genes shown to have an effect when deleted or duplicated. The second indicates regions of the chromosome associated with specific clinical effects for which the causative gene(s) has yet to be identified. They do not include data on genes that have no effect or are merely risk factors for disease.
If you use information from our Gene Dosage Maps in a publication, please cite us: Cody JD, Heard P, Rupert D, Hasi-Zogaj M, Hill A, Sebold C, Hale DE. (2018) Chromosome 18 Gene Dosage Map 2.0 Hum Genet 137(11):961-970. doi:10.1007/s00439-018-1960-6.
