These data suggest that it may be possible to construct high and low risk haplotypes, which may be helpful in DNA analysis and genetic counselling for HD, and represent independent evidence that the gene for HD is centromeric to more distally located DNA markers such as D4S90.
This locus is closely linked to Huntington disease and has been mapped to chromosome 4 short arm using human-mouse somatic cell hybrids, and specifically to chromosome 4 band p16 using DNA from individuals with deletions of chromosome 4 short arm who exhibit Wolf-Hirschhorn syndrome.
This locus is closely linked to Huntington disease and has been mapped to chromosome 4 short arm using human-mouse somatic cell hybrids, and specifically to chromosome 4 band p16 using DNA from individuals with deletions of chromosome 4 short arm who exhibit Wolf-Hirschhorn syndrome.
Three D4S10 restriction-fragment-length polymorphisms produced by the HindIII, EcoRI, and Bg/I enzymes were used for all tests, and the probability that a subject was a Huntington's disease carrier was calculated.
The D4S98/S114/S113 cluster therefore represents the nearest cloned sequences to HD, and provides a valuable new point for launching directional cloning strategies to isolate and characterize this disease gene.
Restriction fragment length polymorphisms for D4S113 and D4S114, one of which is identical to a SacI polymorphism detected by the anonymous probe pBS731B-C (D4S98), were typed for key crossovers in HD and reference pedigrees.
Close genetic linkage has been shown between the DNA sequence G8 (locus D4S10) and 16 British families with Huntington disease using the HindIII, EcoR1, Nci1, and Pst1 polymorphisms detected by G8, and by combining all the polymorphisms to give a combined haplotype.
Somatostatin, substance P, cyclic AMP and cyclic GMP were determined in the cerebrospinal fluid of patients with Huntington's disease, in first generation relatives of choreic patients and in neurological control patients.
Huntington's disease (HD) is an autosomal dominant neurodegenerative disorder caused by an expanding polyglutamine repeat in the IT15 or huntingtin gene.
INTRODUCTION--The discovery of an expansion of a trinucleotide (CAG) repeat region in the IT15 gene on the short arm of chromosome 4 has identified the mutational mechanism causing Huntington's disease (HD) and enables the direct diagnosis of affected subjects based on DNA analysis alone.
In brain tissue from HD heterozygotes with adult onset and more clinically severe juvenile onset, where the largest expansions occur, a mutant protein of equivalent intensity to wild-type huntingtin was detected in cortical synaptosomes, indicating that a mutant species is synthesized and transported with the normal protein to nerve endings.
Both alleles of the IT15 protein were expressed at similar levels in HD lymphoblastoid cell lines and HD post-mortem hippocampus and cerebellum (regions relatively spared in HD), indicating that even very long CAG repeats can be translated into polyglutamine.
Huntington's disease (HD) is a dominant neurodegenerative disorder caused by expansion of a CAG repeat in the gene encoding huntingtin, a protein of unknown function.
Factors that determine the nature of symptoms at onset and the mode of progression of Huntington's disease seem to be operating independently of the (CAG)n trinucleotide repeat in gene IT15.
The differences in SCA1 allele heterogeneity between sperm and blood and within the brain parallels the findings in Huntington disease, suggesting that both disorders share a common mechanism for tissue-specific instability.
The reduction in expression of PPE mRNA suggests that surviving striatal neurons may be affected by the expression of the Huntington's disease gene prior to their imminent cell death.
In order to determine whether the exon containing the expanded CAG repeat is present in IT-15 mRNA from HD patients, we amplified across this region and demonstrated the presence of the expanded repeat in cDNA from both striatum and cortex.