RESUMO
SUCLA2 is one of several nuclear-encoded genes that can cause encephalomyopathy accompanied by mitochondrial DNA depletion. The disorder usually manifests in early childhood and leads to early death. The gene encodes one of the subunits of succinyl-CoA synthase, the enzyme that catalyzes the reversible conversion of substrates succinyl-CoA and ADP to products succinate and ATP in the tricarboxylic acid pathway. Thirty-two individuals harboring mutations in SUCLA2 have so far been reported, and five different mutations were observed among these individuals. Here we report identification of a novel mutation in SUCLA2 in two cousins affected with encephalomyopathy. The novel mutation causes p.Asp251Asn; the affected amino acid is likely positioned within the ATP-grasp domain of the encoded protein. As previously reported in other patients, we did not observe elevation of methylmalonic acid, the biochemical hallmark of patients with mutations in SUCLA2. We instead found elevated levels of succinylcarnitine.
Assuntos
Substituição de Aminoácidos/genética , Carnitina/análogos & derivados , Carnitina/metabolismo , Encefalomiopatias Mitocondriais/enzimologia , Mutação/genética , Succinato-CoA Ligases/genética , Adulto , Encéfalo/patologia , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Imageamento por Ressonância Magnética , Masculino , Linhagem , Succinato-CoA Ligases/químicaRESUMO
Genetic polymorphisms have been shown to be involved in dopaminergic neurotransmission. This may influence susceptibility to Parkinson's disease (PD). We performed a case-control study of the association between PD susceptibility and a genetic polymorphism of MAOB and COMT, both separately and in combination, in Iranians. The study enrolled 103 Iranian patients with PD and 70 healthy individuals. Polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) methods were used for genotyping. Our data indicated that the MAOB genotype frequencies in PD patients did not differ significantly from the control group. However, the frequency of MAOB GG genotype was significantly lower in female patients. It has been shown that the distribution of MAOB allele A was slightly higher in PD patients. No statistically significant differences were found in the COMT allele and genotype distribution in PD patients in comparison to the controls. The combined haplotype of the MAOB A, A/A and COMT LL genotype showed a slight increase in the risk of PD in female patients in this Iranian population. The data may suggest that the MAOB and COMT genetic polymorphisms do not play any role in the pathogenesis of PD in Iranians. In addition, the combined haplotype of MAOB and COMT genes did not significantly affect the susceptibility to PD. Future studies involving larger control and case populations will undoubtedly lead to a more thorough understanding of the role of the polymorphisms involved in the dopamine pathway in PD.
Assuntos
Catecol O-Metiltransferase/genética , Monoaminoxidase/genética , Doença de Parkinson/enzimologia , Doença de Parkinson/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Predisposição Genética para Doença , Genótipo , Humanos , Irã (Geográfico) , Masculino , Pessoa de Meia-Idade , Polimorfismo de Fragmento de Restrição , Polimorfismo de Nucleotídeo Único , Reação em Cadeia da Polimerase Via Transcriptase ReversaRESUMO
BACKGROUND: There is no documented demographical study on Iranian Parkinson's disease (PD) patients, so this study was conducted to identify demographic information about patients with PD in Iran, and to explore demographical differences between PD patients in Iran and other countries. METHODS: We reviewed medical records of 1656 patients diagnosed with PD, who referred from all parts of Iran to a referral Parkinson's disease clinic in Tehran. We collected data about their age, gender, age of onset, side of motor symptoms' onset, and drug history. RESULTS: This study was performed on 1656 patients with idiopathic Parkinson's disease, and the results showed that, out of 1656 cases, 1132 patients were males (68.4%) and 524 patients were females (31.6%). The mean age of these patients was 65.16 ±11.9 years (16-99 years). The mean age of onset in these patients was 53.16 ±12.5 years (12-90 years). Among 697 patients, 345 patients (49.5%) had right onset PD, and the remaining 352 cases had left onset PD (50.5%). Side of motor symptoms onset was not associated with the age of the patients at disease onset (P > 0.05). The incidence of right onset PD in males was 50.1% and 48.2% in females, although this difference was not statistically significant (P > 0.05). There was no significant difference between males and females in age of onset (P > 0.05). CONCLUSION: Our data suggests that the male to female ratio among Iranian Parkinson's disease patients is much higher than other countries. Additional investigation is required in this field.
