Spectrum of pathologic mitochondria DNA mutations in Chinese patients with Leber′s hereditary optic neuropathy / 中华眼底病杂志

Objective To investigate the spectrum of mitochondrial DNA (mtDNA) mutations in Chinese patients with Leber′s hereditary optic neuropathy (LHON). Methods The primary mtDNA mutations (G3460A?G11778A and T14484C) of 140 patients with LHON were detected by mutation-specific priming polymerase chain reaction (MSP-PCR), heteroduplex-single strand conformation polymorphism polymerase chain reaction (HA-SSCP), restriction fragment length polymorphisms (RFLP) and measurement of DNA sequence. The transmissibility of the patients′ stirps was analyzed. Results In the 140 patients with LHON, G11778A mtDNA primary mutation was found in 130 (92.9%), including 113 males and 17 females; G3460A mutation was found in 2 (1.4%) including 1 male and 1 female; G14484A mutation was found in 8 (5.7%) including 6 males and 2 females. Conclusion In Chinese patients with LHON, the incidence of G11778A mtDNA mutation is higher than that of G3460A and T14484C.

Comparison of computer-photoscreening with non-cycloplegic retinoscopy for amblyopiogenic risk factors in children / 眼科新进展

Objective　To determine the sensitivity and specificity of using the computer-photoscreener and non-cycloplegic retinoscopy in the detection of amblyopiogenic factors in nine to fifty months old infants.Methods　Three hundred children whose ages range from nine to fifty months were screened with the computer-photoscreener and non-cycloplegic retinoscopy. With a masked standardized clinical assessment as the standard, an overall comparison of the results obtained with the two techniques revealed a sensitivity and specificity. Photoscreen images on the computer monitor screen were reviewed and analyzed immediately by two independent observers for indicators of amblyopiogenic risk factors. Simultaneously, the results were compared to the findings of a full ophthalmologic examination.Results　The computer-photoscreener revealed a sensitivity of 94.2% and specificity of 90.1%, and the non-cycloplegic retinocopy revealed a sensitivity of 85.7% and specificity of 81.1% for the detection of amblyopiogenic risk factors, including hyperopia (+2.75 D or more), myopia (-1.50 D or more), astigmatism (2.00 D or more),anisometropia (2.00 D or more), ocular misalignment (5 degrees or more), and media opacity (1.5mm or more). Conclusion　The computer-photoscreener offers an opportunity to identify problems that limit vision, and could provide a feasible and sufficiently reliable screening technique in infants and preschool children who can be screened successfully for amblyopiogenic risk factors.

New primary mutation of mtDNA in Leber′s hereditary optic neuropathy / 中华眼底病杂志

Objective To analyze the new primary mutation in Chinese people with Leber′s hereditary optic neuropathy (LHON). Methods Genomic DNA was collected from 260 suspected LHON patients and 100 normal healthy persons. The mitochondria DNA mutation at nucleotide position (NP) 15257 and the hot spot (14452-14601 bp) of ND6 gene which include the mutations at NP (14482, 14498, 14568, 14596, 14495, and 14459) were screened by using polymerase chain reaction (PCR), heteroduplex-single strand conformation polymorphism (HA-SSCP) and restriction fragment length polymorphism (RFLP) analysis and sequencing. Primary mutation spectrum of Chinese race was analyzed. Results Eight kinds of polymorphism of mitochondria DNA were found in 260 suspected LHON patients and 100 normal healthy persons, including NP 14488C, 14518G, and 14617G which hadn't been reported (http://www.mitomap.org/). No mutation at NP 15257, 14482, 14498, 14568, 14596, 14495, and 14459 was found. Conclusion The NP 15257A may not be the primary mutation in Chinese. Because of the race difference, 14452-14601 bp in ND6 gene may not be the hot spot in Chinese patients with LHON, and other hot spots may exist.

SNPs analysis of the METTL4 gene in high myopia groups / 中国病理生理杂志

AIM: To investigate the single nucleotide polymorphisms (SNPs) in the METTL4 gene which was mapped to 18p11.31, and the relationship between the SNPs and high myopia. METHODS: Genomic DNA was collected from 71 control subjects and 177 individuals with high myopia. Among them, there were 59 autosomal dominant high myopia probands (AD group), 46 autosomal recessive probands (AR group) and 72 patients non-transmitted (SF group). The exons of METTL4 gene were analyzed by polymerase chain reaction, heteroduplex-single strand conformation polymorphism (HA-SSCP) and sequencing. RESULTS: There were 2 SNPs of METTL4 gene in high myopia individuals and control subjects: SNP7438A→C, Glu230Asp, which hadn't been reported in GenBank;and SNP131C→A, Gln310Lys. SNP7438A→C genotypes between controls and high myopia groups were not different. SNP131C→A genotypes between controls and AR or SF groups were not different, while SNP131C→A genotypes showed a significant difference between AD group and control subjects. CONCLUSION: In METTL4 gene, SNP7438A→C is not responsible for high myopia. Further studies are needed to confirm whether SNP131C→A is responsible for autosomal dominant high myopia.

A missense mutation outside the large pocket of the retinoblastoma protein / 中国病理生理杂志

AIM: To understand the effect of the RB1 gene mutation on the function of pRB (the protein product of the RB1 gene) in the patients with retinoblastoma (RB). METHODS: The genomic DNA from retinoblastoma patients was extracted. After amplification, the promoter and all 27 exons were screened by SSCP-heteroduplex method. The mutation was cloned and identified by sequencing. The effect of the mutation product on the function of pRB was analyzed. RESULTS: One missense mutations of the exon 4 of the RB1 gene was identified in the genomic DNA from RB patients. This mutation was outside the large pocket of the pRB. No mutation of the RB1 gene was found in the genome DNA of the patient's parents. This is the fourth report that there was a genome mutation located outside the large pocket of pRB in the RB patients. CONCLUSION: The amino-terminus of the pRB may be essential for growth suppression.