HOXD13 and androgen insensitivity syndrome: In our studies, we chose androgen receptor (Ar) and homeobox D13 (Hoxd13) as targeted genes, and generated two mouse models, androgen insensitivity syndrome (AIS) and Syndactyly, by introducing A to G conversions at corresponding homologous pathogenic sites of patients through microinjection of mRNA and sgRNAs into zygotes.