Haploinsufficiency of is likely to contribute to developmental delay involving 14q13 microdeletions.

Nucleotide variations or deletions in the NK2 homeobox 1 gene (), located at 14q13.3, lead to symptoms associated with the brain, lungs, and thyroid, and the combination of these phenotypes is clinically recognized as the brain-lung-thyroid syndrome. Many types of nucleotide variants of have been identified, and phenotypic variability has been reported.