RESUMO
PURPOSE: To screen for mutations in the coding region of the myocilin (MYOC) gene in a large Malay family with juvenile-onset open angle glaucoma (JOAG). METHODS: A total of 122 family members were thoroughly examined and screened for JOAG. Venipuncture was conducted. Genomic DNA was extracted from peripheral blood leukocytes. The presence of a mutation and a polymorphism was ascertained with PCR amplification followed by the direct sequencing technique. RESULTS: Thirty-two of the 122 screened family members were identified to have JOAG (11 new cases and 21 known cases). An autosomal dominant inheritance pattern with incomplete penetrance was observed. A CâA substitution at position 1440 in exon 3 that changes asparagine (AAC) to lysine (AAA) was identified in affected family members except two probands (III:5 and IV:6). Six probands were identified as having the Asn480Lys mutation but have not developed the disease yet. An intronic polymorphism IVS2 730 +35 G>A was also identified. There was a significant association between Asn480Lys (p<0.001) and IVS2 730+35G>A (p<0.001) in the affected and unaffected probands in this family. CONCLUSIONS: The Asn480Lys mutation and the IVS2 730+35 G>A polymorphism increased susceptibility to JOAG in this large Malay pedigree. Identifying the MYOC mutations and polymorphisms is important for providing presymptomatic molecular diagnosis.
Assuntos
Proteínas do Citoesqueleto/genética , Proteínas do Olho/genética , Predisposição Genética para Doença , Glaucoma de Ângulo Aberto/epidemiologia , Glaucoma de Ângulo Aberto/genética , Glicoproteínas/genética , Mutação/genética , Polimorfismo de Nucleotídeo Único/genética , Adolescente , Adulto , Idade de Início , Idoso , Sequência de Bases , Criança , Eletrorretinografia , Família , Feminino , Frequência do Gene/genética , Estudos de Associação Genética , Glaucoma de Ângulo Aberto/fisiopatologia , Humanos , Malásia/epidemiologia , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Linhagem , Adulto JovemRESUMO
The presenting signs of acute leukaemia occur as a result of bone marrow failure and organ infi ltration. Increased bleeding tendencies are seen on the skin, gums and mucosal lining. Bleeding in the posterior segment of the eye, namely the retina and vitreous, may occur, but do not usually cause any visual disturbances. This case demonstrates visual loss as a result of premacular subhyaloid haemorrhage in acute leukaemia.
