Huntington's disease (HD) has recently been found to be caused by expansion of a trinucleotide (CAG) repeat within the putative coding region of a gene with an unknown function. We report here an analysis of HD mutation and the characteristics of its transmission in 36 HD families. CAG repeats on HD chromosomes were unstable when transmitted from parent to offspring. Instability appeared more f...

Analysis of the distribution of normal and expanded alleles of the polymorphic (CAG)n repeat in the IT15 gene in the Dutch population confirmed the presence of an expanded repeat on all Huntington's disease (HD) chromosomes. Our results show that the size distributions of normal and affected alleles overlap. Normal alleles range from 11 to 37 repeats and HD alleles contain 37 to 84 repeats. A c...

EDITOR—Mutations of the BRCA1 and BRCA2 tumour suppressor genes have been identified in some cases of familial and early onset breast cancer. 2 Mutations of these genes, however, account for a relatively small proportion of the total cases of female breast cancer. Male breast cancer is a very rare disease, accounting for approximately 1% of all cases of breast cancer. Less is known about the ge...

EDITOR—Mutations of the BRCA1 and BRCA2 tumour suppressor genes have been identified in some cases of familial and early onset breast cancer. 2 Mutations of these genes, however, account for a relatively small proportion of the total cases of female breast cancer. Male breast cancer is a very rare disease, accounting for approximately 1% of all cases of breast cancer. Less is known about the ge...

Trinucleotide repeat (TNR) expansions cause at least 17 heritable neurological diseases, including Huntington's disease. Expansions are thought to arise from abnormal processing of TNR DNA by specific trans-acting proteins. For example, the DNA repair complex MutSβ (MSH2-MSH3 heterodimer) is required in mice for on-going expansions of long, disease-causing alleles. A distinctive feature of TNR ...

Abstract Expansions of CAG/CTG trinucleotide repeats in DNA are the cause at least 17 degenerative human disorders, including Huntington’s Disease. Repeat instability is thought to occur via formation intrastrand hairpins during replication, repair, recombination, and transcription though relatively little known about their structure dynamics. We use single-molecule Förster resonance energy tra...

CONTEXT Machado-Joseph disease (MJD/SCA3) is an autosomal dominant cerebellar ataxia of adult onset. The variability in age at onset and the complex and heterogeneous neurologic findings indicate that MJD, caused by a major gene, is modulated by modifier factors. OBJECTIVE To study if the polymorphic CAG repeats at other loci (namely, SCA2, SCA6 and DRPLA) thus acted as modifier factors of th...

EDITOR—Mutations of the BRCA1 and BRCA2 tumour suppressor genes have been identified in some cases of familial and early onset breast cancer. 2 Mutations of these genes, however, account for a relatively small proportion of the total cases of female breast cancer. Male breast cancer is a very rare disease, accounting for approximately 1% of all cases of breast cancer. Less is known about the ge...

EDITOR—Mutations of the BRCA1 and BRCA2 tumour suppressor genes have been identified in some cases of familial and early onset breast cancer. 2 Mutations of these genes, however, account for a relatively small proportion of the total cases of female breast cancer. Male breast cancer is a very rare disease, accounting for approximately 1% of all cases of breast cancer. Less is known about the ge...