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A common gene for juvenile and adult-onset primary open-angle glaucomas confined on chromosome 1q. 总被引:11,自引:2,他引:9 下载免费PDF全文
J Morissette G Ct J L Anctil M Plante M Amyot E Hon G E Trope J Weissenbach V Raymond 《American journal of human genetics》1995,56(6):1431-1442
Primary open-angle glaucoma (POAG), which causes progressive loss of the visual fields, was subdivided into two groups according to age at onset: (1) chronic open-angle glaucoma (COAG) diagnosed after age 40 years and (2) juvenile open-angle glaucoma (JOAG) diagnosed between 3 years of age and early adulthood. A JOAG gene (GLC1A) was recently mapped to chromosome 1q. We studied 142 members of a huge multigenerational French Canadian family affected with autosomal dominant POAG. Either JOAG or COAG was diagnosed in 40 patients. Six subjects were also diagnosed with ocular hypertension (OHT), which may lead to POAG. To localize a common disease gene that might be responsible for both glaucoma subsets, we performed linkage analysis considering JOAG and COAG under the same phenotypic category. JOAG/COAG was tightly linked to seven microsatellite markers on chromosome 1q23-q25; a maximum lod score of 6.62 was obtained with AF-M278ye5. To refine the disease locus, we exploited a recombination mapping strategy based on a unique founder effect. The same characteristic haplotype, composed of 14 markers spanning 12 cM between loci D1S196 and D1S212, was recognized in all persons affected by JOAG, COAG, or OHT, but it did not occur in unaffected spouses and in normal family members > 35 years of age, except for three obligatory carriers. Key recombination events confined the disease region within a 9-cM interval between loci D1S445 and D1S416/D1S480. These observations demonstrate that the GLC1A gene is responsible for both adult-onset and juvenile glaucomas and suggest that the JOAG and COAG categories within this family may be part of a clinical continuum artificially divided at age 40 years. 相似文献
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Summary A protocol was developed for the preparation of Cucumis sativus var Straight 8 protoplasts that incorporates a two-step Ficoll® gradient and results in a high percentage of viable, debris-free protoplasts suitable for the transient expression of foreign genes. Polyethylene glycol and electroporation were compared for their effect on protoplast transfection with commonly used reporter genes. Using a polyethylene glycol method, cucumber protoplasts transfected with a plasmid containing the -glucuronidase gene showed high expression levels, while protoplasts transfected with a plasmid containing the chloramphenicol acetyl transferase gene showed levels of activity that were barely distinguishable from mock-transfected controls. Tomato ringspot virus genomic RNA was also transfected into the protoplasts, and the assembly of viral particles was confirmed. 相似文献
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M. L. Kottler F. Lorenzo F. Bergametti P. Commerçon C. Souchier R. Counis 《Human genetics》1995,96(4):477-480
We have isolated nine yeast artificial chromosomes (YACs) containing the gene that encodes the human gonadotropin-releasing hormone receptor (GnRH-R) gene by screening the YAC library of the Centre d'Etude du Polymorphisme Humain (Hôpital Saint-Louis, Paris, France) by the use of the polymerase chain reaction. We defined the location of the GnRH-R gene relative to 4q microsatellite markers D4S392 and D4S409. The genetic positions of these markers on chromosome 4 are 76 and 77 cM, respectively. This location was further established by chromosomal in situ hybridization. 相似文献
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25 populations from Turkey and one of Syria belonging to theSabulina section of the genusMinuartia have been karyologically examined. New chromosome numbers have been recorded forM. mesogitana andM. hybrida subsp.turcica, and a new variety was found in theM. hybrida complex. The origin of the taxa with n = 23 and n = 35 is discussed. 相似文献
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The restriction enzymes AluI, BamHI, BglII, EcoRI, HindIII, and SalI have been used to characterize and map a new cauliflower mosaic virus strain (Cabb-S). These fragments have been ordered by examining their overlapping regions after double enzymatic digestion. The single SalI cleavage site was chosen as the point of origin. We compare this strain with those already described. 相似文献
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M Potier P Guay P Lamothe D Bousquet L Dallaire S B Melan?on 《Journal of reproduction and fertility》1979,57(1):49-57
Intestinal lactase activity (with its associated cellobiase, 4-methylumbelliferyl-beta-galactosidase and -beta-glucosidase activities) was used as a specific intestinal marker enzyme to study the release of protein and enzymes of intestinal origin in sheep amniotic fluid during gestation. In amniotic fluid, intestinal lactase activity peaked at 66--85 days of gestation and then decreased with gestation. This enzyme activity was very low or absent in allantoic fluid throughout gestation suggesting that there is no important transfer of amniotic fluid lactase towards the allantoic cavity. Maltase and 4-methylumbelliferyl-alpha-glucosidase showed no statistically significant variation with gestation in both amniotic and allantoic fluid whereas alpha-galactosidase and N-acetyl-beta-hexosaminidase which were first higher in allantoic than in amniotic fluid increased in amniotic fluid to reach allantoic fluid levels near term. Such patterns are consistent with the suggestion that the fetal urine is a source of alpha-galactosidase and N-acety-beta-hexosaminidase activities and that sheep urine is first accumulated in the allantoic sac via the urachus up to 86--90 days of gestation and thereafter passes more and more into the amniotic sac. 相似文献