Chd7, or Chromodomain helicase DNA-binding protein 7, is an ATP-dependent eukaryotic chromatin remodeling enzyme. It is essential for the development of multiple organs. Its function is related to various biological processes, and its associated pathways include the regulation of gene expression through chromatin remodeling. Genetic models, such as KO/CKO mouse models, are valuable for studying its functions [1,2,3,4,6,8,9].

Conditional knockout of Chd7 in bone marrow mesenchymal stem cells and preosteoblasts in mice leads to low bone mass and high marrow adiposity, due to enhanced peroxisome proliferator-activated receptor (PPAR) signaling as Chd7 loss reduces the restriction of PPAR-γ [1]. In the heart, Chd7 haploinsufficiency in mouse models reveals its role in multiple lineages during heart development, like in the formation of great vessels and atrioventricular cushion development [2]. In the inner ear of mice, combined haploinsufficiency for Chd7 and Sox2 results in reduced otic cell proliferation, malformations of semicircular canals, and cochlear defects, with CHD7 regulating Sox2 expression and acting in a gene regulatory network [4]. Deletion of Chd7 in oocytes of mice causes infertility or sub-fertility, along with decreased follicle numbers and increased granulosa cell apoptosis [6].

In conclusion, Chd7 plays crucial roles in the development of various organs including bones, heart, eyes, inner ear, and female reproductive system. The KO/CKO mouse models have significantly contributed to understanding its functions in related disease conditions such as CHARGE syndrome, skeletal disorders, heart defects, inner ear-related hearing or balance disorders, and female infertility [1,2,3,4,5,6,7,8,9].