In addition, in 2 cases (2/33) the following likely pathogenic causative variants were also inherited: (i) a variant maternally inherited in the FGD1 gene associated to recessive X-linked syndromic mental retardation 16 (#305400) and (ii) a frameshift variant in the CLTC gene inherited from the apparently unaffected mother associated to autosomal dominant mental retardation 56 (#617854), a disorder with highly variable severity. This evidence concerns the gene FGD1 and Rare genetic intellectual disability with developmental anomaly.