Objective: Vacuolating megalencephalic leukoencephalopathy with subcortical cysts (MLC) is a recently described syndrome with autosomal recessive mode of inheritance. Its possible gene was located on chromosomal 22q ...Objective: Vacuolating megalencephalic leukoencephalopathy with subcortical cysts (MLC) is a recently described syndrome with autosomal recessive mode of inheritance. Its possible gene was located on chromosomal 22q tel with 3-cM. The purpose of this study was to narrow down the genetical distance on chromosomal 22q tel with MLC. Methods: Thirty-nine MLC patients in 33 families were collected,and the linkage analysis and haplotype analysis of twelve informative families were done, using seven microsatellite markers and four SNP markers. Results: The maximum tow-point LOD score for marker 355c18 was 6.65 at recombination fraction 0.02. The haplotype analysis narrowed down the critical region of MLC to 250 kb on chromosomal 22q tel. Conclusion: One of the causing genes of MLC was located on chromosomal 22q tel with 250 kb. Four candidate genes were considered. The heterogeneity of one informative family indicated possible existence of a second locus for MLC.展开更多
Hereditary fructose intolerance(HFI) is an underrecognized,preventable life-threatening condition.It is an autosomal recessive disorder with subnormal activity of aldolase B in the liver,kidney and small bowel.Symptom...Hereditary fructose intolerance(HFI) is an underrecognized,preventable life-threatening condition.It is an autosomal recessive disorder with subnormal activity of aldolase B in the liver,kidney and small bowel.Symptoms are present only after the ingestion of fructose,which leads to brisk hypoglycemia,and an individual with continued ingestion will exhibit vomiting,abdominal pain,failure to thrive,and renal and liver failure.A diagnosis of HFI was made in a 50-year-old woman on the basis of medical history,response to fructose intolerance test,demonstration of aldolase B activity reduction in duodenal biopsy,and molecular analysis of leukocyte DNA by PCR showed homozygosity for two doses of mutant gene.HFI may remain undiagnosed until adult life and may lead to disastrous complications following inadvertent fructose or sorbitol infusion.Several lethal episodes of HFI following sorbitol and fructose infusion have been reported.The diagnosis can only be suspected by taking a careful dietary history,and this can present serious complications.展开更多
文摘Objective: Vacuolating megalencephalic leukoencephalopathy with subcortical cysts (MLC) is a recently described syndrome with autosomal recessive mode of inheritance. Its possible gene was located on chromosomal 22q tel with 3-cM. The purpose of this study was to narrow down the genetical distance on chromosomal 22q tel with MLC. Methods: Thirty-nine MLC patients in 33 families were collected,and the linkage analysis and haplotype analysis of twelve informative families were done, using seven microsatellite markers and four SNP markers. Results: The maximum tow-point LOD score for marker 355c18 was 6.65 at recombination fraction 0.02. The haplotype analysis narrowed down the critical region of MLC to 250 kb on chromosomal 22q tel. Conclusion: One of the causing genes of MLC was located on chromosomal 22q tel with 250 kb. Four candidate genes were considered. The heterogeneity of one informative family indicated possible existence of a second locus for MLC.
文摘Hereditary fructose intolerance(HFI) is an underrecognized,preventable life-threatening condition.It is an autosomal recessive disorder with subnormal activity of aldolase B in the liver,kidney and small bowel.Symptoms are present only after the ingestion of fructose,which leads to brisk hypoglycemia,and an individual with continued ingestion will exhibit vomiting,abdominal pain,failure to thrive,and renal and liver failure.A diagnosis of HFI was made in a 50-year-old woman on the basis of medical history,response to fructose intolerance test,demonstration of aldolase B activity reduction in duodenal biopsy,and molecular analysis of leukocyte DNA by PCR showed homozygosity for two doses of mutant gene.HFI may remain undiagnosed until adult life and may lead to disastrous complications following inadvertent fructose or sorbitol infusion.Several lethal episodes of HFI following sorbitol and fructose infusion have been reported.The diagnosis can only be suspected by taking a careful dietary history,and this can present serious complications.
