FBXW4 and split hand-foot malformation: Seven types of non-syndromic SHFM have been mapped on different human chromosomes.Four of these forms (SHFM-1, SHFM-3, SHFM-4, SHFM-5) inherit in autosomal dominantpattern, SHFM-2 in X-linked inherited, and SHFM-6 in autosomal recessive pattern.The four autosomal dominant forms were mapped on chromosome 7q21 (SHFM-1; MIM183600)(Scherer et al., 1994),10q24 (SHFM-3; MIM246560) (Nunes etal., 1995; Gurrieriet al., 1996; Raas-Rothschild et al., 1996), 3q27 (SHFM-4; MIM605289)(Ianakiev et al., 2000)and 2q31 (SHFM-5; MIM606708) (Boles etal., 1995).