Abstract: Objective To develop a rapid, reliable and convenient approach for diagnosing Coffin-Lowry Syndrome(CLS). Methods RNA and DNA were extracted from the CLS patients' fresh peripheral blood. The fragments of RPS6KA3 cDNA were amplified by RT-PCR and sequenced. The mutation was verified at the DNA level. The other case that failed to detect the nucleotide change was tested by multiplex ligation-dependent probe amplification (MLPA). Results A two nucleotide deletion (r889_890delAG) in RPS6KA3 gene was detected in the first case, while there was no change in the other boy. The nucleotide sequence of the first case's mother was normal, implying that it was a de novo mutation. Conclusion This was the first time that CLS was diagnosed by molecular method in China, which provided a genetic basis for gene diagnosis and prenatal diagnosis of CLS.

Key words: Coffin-Lowry syndrome, RPS6KA3, RSK2, RT-PCR, MLPA