Fig. 4

Hemizygous mutations identified by sequencing analysis of the CHST6 gene. A Missense mutation of c.520A>C (p.K174Q) in CHST6 of the proband. The single peak of c.520C revealed that the c.520A>C mutation of the proband was homozygous or hemizygous. B Normal sequences of CHST6 (Reference Sequence: NM_021615) and the CHST6 sequences of the proband’s son (III-3). The sequense of C.520A revealed that the III-3 was normal or hemizygous carrier. C The CHST6 sequences of the proband’s daughter (III-4). The two peaks of c.520A and c.520C showed the III-4 was a heterozygous carrier. D Target exome sequencing revealed a heterozygous deletion of exon 3 of CHST6 as indicated by the red circle. And the deletion of exon3 was detacted from the proband and the son. The TAT gene located on 16q22.2, and the ADAMTS18 gene located on 16q23.1. The ratio of CHST6 was obviously lower than the TAT and ADAMTS18 genes, which showed the deletion of exon 3. E, F Multiple sequence alignment analysis between human CHST1-7 protein and other sulfotransferases of animals demonstrated that the novel mutation substituted relatively well-conserved amino acid residues. The red arrows indicate the position of the c.520A>C mutation, and the blue arrow indicates the position of the normal sequence