Sequence alignment of fibulin-4 and location of mutations. A:Multiple sequence alignment of fibulin-4 protein sequence from (1) Homo sapiens, (2) Pan troglodytes*, (3) Canis lupus familiaris*, (4) Bos taurus, (5) Mus musculus,(6) Danio rerio ; sequences from species marked * were computationally predicted. cbEGF4 sequence is enclosed in the rectangular box.Substitutions within the domain are encircled. Arrow marks the position of aspartate 203 in human fibulin-4. Conservation of amino acid identity of this aspartate across species and its sequence position at start of the cbEGF4 domain, indicates its functional significance. All patients had identical missense mutation at this crucial position. B : Schematic representation of domains, based on Swiss-Prot annotation [Swiss-Prot:O95967]. The types of domain are listed on the left. Amino acid position in fibulin 4 sequence is noted at start and end positions of the protein, the atypical cbEGF domain and the region containing 5 tandem cbEGF domains. Mutations listed on the right are found in human disease with the exception of I259V*. The D203A mutation (bold) is the one found in all patients in our cohort. Mutations shown in italics occurred in compound heterozygotes. References are shown in brackets.