ATP7A Genetic Analysis Of13Chinese Patients With Menkes Disease

ObjectiveBy analyzing ATP7A gene mutations,copy number variation（CNV） and clinicaldata about13Chinese patients with Menkes Disease （MD） confirmed by geneticdiagnosis to discuss the relationship of genotype and phenotype,geneticcharacteristics, to learn about common form and hot spot of ATP7A gene mutationin Chinese patients with MD.Method13patients clinically diagnosed Menkes disease were included. DNA of patientsand their family members were extracted from peripheral blood after signed theinformed consent.All23exons and exon-intron boundaries of ATP7A gene were PCR amplified anddirectly sequenced for genomic DNA extracted from peripheral blood. Multiplexligation-dependent probe amplification （MLPA） assays were performed to detectATP7A copy number variation.The patients have diagnosed by genetic diagnosis.ResultsAll Patients are classical Menkes.we report the mutations of ATP7A gene with13chinese patients including11gene mutations, which has3missense mutations（27%）: c.3028A>C（p.T1010P）、 c.2179G>A （p.G727R） and c.3914A>G（p.D1305G）,3splice site mutations（27%）: IVS20+1G>A、IVS20-7delTTCTTand IVS18+1G>A,2small deletions mutations （18%）: c.2589delTGAAGGA+c.2598delTT+c.2601delT+c.2603delT+c.2605delGTAGATGA（p.E864fsX883）and c.3045delT （p.T1016fsX1018）,1gross deletion mutation （9%）: c.2173₂406del （p.F725_K802del）,1nonsense mutation （9%）:c.1642G>T（p.Glu548*）,1small insertion mutation（9%）: c.1642₁643insA（P.Leu549ThrfsX12）.These mutations are not found in the normal100chromosomes.1Patient was detected the big fragment deletion of ATP7A gene byMLPA.ATP7A gene mutations we found have11species, in which2kinds werereported mutations, the others are unreported in ATP7A database（www.LOVD.nl/ATP7A）. It shows China may have special mutation spectrum ofATP7A gene. c.2179G>A （p.G727R） were found in2patients and IVS20+1G>Awere found in the other2patients.Conclusion13Patients are all classical Menkes diease and males. Chinese Patients’ primaryclinical phenotype is consistent with the rest of the country.We indentified thatmothers of7in13patients who are with normal phenotype carried thoseheterozygous mutations in the same site of ATP7A gene. This will help to carry outprenatal diagnosis.c.2179G>A （p.G727R） and IVS20+1G>A may be higherincidence of ATP7A gene mutations with MD in Chinese Patients. With the samemutations c.2179G>A （p.G727R）, P6which was47,XXY/46,XY,had earlier onsetand heavier clinical symptoms than P8which was the normal phenotype.With thesame mutations IVS20+1G>A,1case was onset as epilepsy, the other was onsetas intellectual movement behind.Patients with gross deletion mutation than thosewith small deletion mutation had earlier onset and heavier clinical symptoms.