There is also a considerable overlap with the phenotype associated with pseudohypoparathyroidism type 1A and 1C (Albright hereditary osteodystrophy), acrodysostosis, and chromosome 2q37 deletion syndrome (including brachydactyly-mental retardation syndrome because of loss-of-function variants in the HDAC4). This evidence concerns the gene HDAC4 and brachydactyly.