<正>Increasing cases of 9p syndrome have been reported since the first description in 1970.In the present case

a extra segment of the end of chromosome 9p resulting from a maternally inherited transloca- tion t（4;9）（q31;p24）was described in a liveborn boy with mental retardation and multiple congenital anomalies.The extra part of chromosome 9p includes segment of the chromosome region 4q31→qter of his mother but deletes a small segment 9p24→pter.To our knowledge

this is the first case described in a liveborn child.This paper also includes a review and tabulation of clinical features seen in the 34 reported cases.The new case had most characteristics reported cases besides worried face

fat and abnormal lower digestion tract

which is a modification and double expansion of the previous summarization on 9p syn- drome.