Abstract:

Objective To investigate the genetic abnormalities of Silver-Russell syndrome, to improve the understanding of this disease, and to guide the clinical diagnosis. Methods Two patients who were suspected to have the Silver-Russell syndrome were selected and their medical history was collected in detail and summarized. The DNA of peripheral blood of patients was extracted by the genomic DNA kit and then prepared by the bisulphite conversion process. The target sequence was amplified by the PCR. The methylation status of DMR zone in upstream of H19 imprinted genes of 11P15 area was detected by the pyrophosphate sequencing. The peripheral blood of ten healthy children was collected as controls. Results The clinical characteristics and assistant examinations of two patients accorded with the clinical diagnosis of Silver-Russell syndrome. The methylation levels of six methylation sites of DMR zone in upstream of H19 imprinted genes were 16%-21% and 15%-22%. The methylation status of these areas was low. While the methylation levels of six methylation sites of controls were 48%-55%, which were significantly higher than those of patients. Conclusion The clinical manifestations of Silver-Russell syndrome are diverse. The pyrophosphate sequencing combined with the methylation analysis is easy to operate and can quantify accurately. This technology can be used for examining cases that are clinically diagnosed as SilverRussell syndrome or suspected to have the Silver-Russell syndrome.

Key words: Silver-Russell syndrome, clinical manifestation, H19 imprinted genes, methylation