Correlation between prion protein gene codon 129 polymorphism and late-onset Alzheimer's disease

BACKGROUND： Studies addressing the correlation between prion protein gene codon 129 polymorphism, Alzheimer＇s disease, and cognitive disorders have mainly focused on Caucasians. However, prion protein gene codon 129 polymorphism is thought to also affect the Chinese Han and Wei populations. OBJECTIVE： To analyze the differences of prion protein gene codon 129 distribution among the elderly Chinese Han, East Asian, and Caucasian populations, and to study the correlation between prion protein gene codon 129 distribution and late-onset Alzheimer＇s disease. DESIGN, TIME AND SETTING： A gene polymorphism analysis was performed in the Institute of Geriatrics, General Hospital of Chinese PLA between January 2006 and January 2007. PARTICIPANTS： A total of 152 elderly Chinese Han people were selected from the Beijing Troop Cadre＇s Sanitarium. Among them, 60 patients with late-onset Alzheimer＇s disease, with a mean age of （82 ± 7） years （range 67-94 years） and disease course of （5.9 ± 4.4） years, comprising 44 males with a mean age of （83 ± 7） years and 16 females with a mean age of （78 ±7） years, were selected for the case group. An additional 92 healthy elderly subjects, with a mean of （76 ± 9） years （range 60-94 years）, comprising 76 males with a mean age of （77 ± 9） years and 16 females with a mean age of （70 ± 8） years, were selected for the control group. There were no significant differences in age and gender between the two groups （P〉 0.05）. METHODS： DNA was extracted from peripheral blood leukocytes using routine phenol/chloroform methodology. Prion protein gene codon 129 potymorphism and ApoE polymorphism were measured using PCR-restriction fragment length polymorphism. The ApoEε allele was considered the standard for analyzing correlations between prion protein gene codon 129 polymorphism and late-onset Alzheimer＇s disease. MAIN OUTCOME MEASURES： Prion protein gene codon 129 distribution; correlation between genotypic frequency and allele frequency of prion protein gene codon 129 with Alzheimer＇s disease; relationship between methionine/methionine genotype of priori protein gene, ApoEε4 allele, gender, and age of Alzheimer＇s disease patients. RESULTS： Methionine/methionine genotypic frequency of prion protein gene codon 129 was 94.08% in the Chinese elderly population, and the methionine/valine genotypic frequency was 5.92%. However, valine/valine homozygotes were not determined. There was no significant difference in prion protein gene codon 129 polymorphism between the Chinese elderly and East Asian populations （P〉 0.05）. However, there was a significant difference between the Chinese elderly and the Caucasian population （P 〈 0.05）. The methionine/methionine genotype for the positive and negative ApoEε4 alleles was a risk factor for increased incidence of Alzheimer＇s disease, but there was no significant difference between the positives and the negatives （odds ratio = 1.33, 95% confidence interval = 0.32-6.49, P〉 0.05）. CONCLUSION： Prion protein gene codon 129 distribution in the Chinese elderly was different from the Caucasian population, which suggested that the methionine/methionine genotype of prion protein gene codon 129 negatively correlated with late-onset Alzheimer＇s disease.

少见晚发型庞贝病合并运动神经元受损1例

庞贝病(Pompe disease)亦称糖原贮积病Ⅱ型(GSDⅡ),传统认为它是一种遗传性肌肉病,特征是编码酸性α-葡萄糖苷酶(GAA)的基因突变,其糖原贮积主要在肌肉。但有文献报道庞贝病可见脑血管内皮细胞受损、自主神经功能障碍、周围神经系统和小纤维神经病变。罕见运动神经元受累表现。本文报道1例庞贝病合并运动神经元受损病例,提示庞贝病是一种神经肌肉疾病并文献回顾,以提高临床诊断效率。