CHD7 and Kallmann syndrome: Moreover, mutations of CHD7 have also been identified in about 6% of Kallmann syndrome (OMIM #308700), a developmental disease characterized with IHH (idiopathic hypogonadotropic hypogonadism) and anosmia (Kim et al., 2008; Balasubramanian et al., 2014; Marcos et al., 2014).