临床发现1例智力低下伴轻度发育迟缓的女性患儿，对患儿进行G显带高分辨染色体核型分析, 发现18q21→qter缺失, 经多色荧光原位杂交和双色荧光原位杂交证实, 确定其核型为46,XX,del(18)(pter→q21:),ish del(18)(D18Z1+, qter-)。用DNA多态性方法分析, 该患儿从18q22.1至18qter区域内至少有8.7 Mbp丢失, 有MBP基因和GALNR基因缺失。缺失的18号染色体源自父亲。患者的智力低下和生长发育迟缓是18q21→qter缺失的结果, 或许与MBP基因和GALNR基因的缺失有关。

This study is about a girl with chromosome deletion of 18q and with mental retardation and mild delay of physical development. Based on karyotyping of high resolution, florescence in situ hybridization (FISH) and microsatellite analysis mapping to 18q, we found that the patient’s karyotype was interpreted as 46,XX,del(18).(pter→q21:), ish del(18)(D18Z1+,qter-). Detection of D18S979 showed that the region from 18q21.1 to 18qter was deleted, which was originated from her father. There were MBP gene and GALNR gene in the deleted interval in which both of them were lost. In conclusion, deletion of 18q21→qter including the MBP gene and GALNR gene should be responsible for her mental re-tardation and mild delay of development.