Interestingly, gain-of-function mutations localized in GHKL-ATPase domain of SMCHD1 have been shown to cause severe malformations of the human nose, olfactory tract and eyes (collectively known as Bosma arhinia microphthalmia syndrome; BAMS), whereas LOF or dominant-negative pathogenic SMCHD1 mutations have been found throughout the sequence of the gene [22,23]. This evidence concerns the gene SMCHD1 and arhinia, choanal atresia, and microphthalmia.