Xq22.3-q23 microdeletion is a rare genomic disorder. The purpose of this study is to emphasize the correlation between clinical phenotype and genotype of proximal deletion on chromosome Xq22.3-q23. A 5 years old boy had a 671Kb microdeletion on Xq23 by chromosomal microarray analysis (CMA), including AMMECR1 and CHRDL1 genes. He presented microsomia, midface hypoplasia, right kidney dysplasia and mildly motor retardation, which have never been reported before to be related with Xq23 deletion. To our knowledge, this is the first case with Xq23
microdeletion. A total of 9 cases with microdeletion at Xq22.3-q23 covered AMMECR1 gene and 2 cases with CHRDL1 mutation were reviewed. These data indicated that Xq23 microdeletion with microsomia, midface hypoplasia, kidney dysplasia, mildly motor retardation was rare. The previous literature showed two novel point mutation in AMMECR1 and CHRDL1 with some phenotype different from the patient. Xq23 microdeletion should be considered for patients with microsomia, midface hypoplasia, kidney dysplasia and growth retardation.