Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
14
pubmed:dateCreated
2000-9-29
pubmed:abstractText
We recently described an untranslated CTG expansion that causes a previously undescribed form of spinocerebellar ataxia (SCA8). The SCA8 CTG repeat is preceded by a polymorphic but stable CTA tract, with the configuration (CTA)(1-21)(CTG)(n). The CTG portion of the repeat is elongated on pathogenic alleles, which nearly always change in size when transmitted from generation to generation. To better understand the reduced penetrance and maternal penetrance bias associated with SCA8 we analyzed the sequence configurations and instability patterns of the CTG repeat in affected and unaffected family members. In contrast to other triplet repeat diseases, expanded alleles found in affected SCA8 individuals can have either a pure uninterrupted CTG repeat tract or an allele with one or more CCG, CTA, CTC, CCA or CTT interruptions. Surprisingly, we found six different sequence configurations of the CTG repeat on expanded alleles in a seven generation family. In two instances duplication of CCG interruptions occurred over a single generation and in other instances duplications that had occurred in different branches of the family could be inferred. We also evaluated SCA8 instability in sperm samples from individuals with expansions ranging in size from 80 to 800 repeats in blood. Surprisingly the SCA8 repeat tract in sperm underwent contractions, with nearly all of the resulting expanded alleles having repeat lengths of <100 CTGs, a size that is not often associated with disease. These en masse repeat contractions in sperm likely underlie the reduced penetrance associated with paternal transmission.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0964-6906
pubmed:author
pubmed:issnType
Print
pubmed:day
1
pubmed:volume
9
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
2125-30
pubmed:dateRevised
2011-11-17
pubmed:meshHeading
pubmed-meshheading:10958651-Alleles, pubmed-meshheading:10958651-Blotting, Southern, pubmed-meshheading:10958651-Family Health, pubmed-meshheading:10958651-Fathers, pubmed-meshheading:10958651-Female, pubmed-meshheading:10958651-Gene Duplication, pubmed-meshheading:10958651-Humans, pubmed-meshheading:10958651-Male, pubmed-meshheading:10958651-Models, Genetic, pubmed-meshheading:10958651-Mothers, pubmed-meshheading:10958651-Nerve Tissue Proteins, pubmed-meshheading:10958651-Pedigree, pubmed-meshheading:10958651-Penetrance, pubmed-meshheading:10958651-RNA, Untranslated, pubmed-meshheading:10958651-Sequence Analysis, DNA, pubmed-meshheading:10958651-Spermatozoa, pubmed-meshheading:10958651-Spinocerebellar Ataxias, pubmed-meshheading:10958651-Trinucleotide Repeat Expansion, pubmed-meshheading:10958651-Trinucleotide Repeats
pubmed:year
2000
pubmed:articleTitle
SCA8 CTG repeat: en masse contractions in sperm and intergenerational sequence changes may play a role in reduced penetrance.
pubmed:affiliation
Department of Genetics, Cell Biology and Development, University of Minnesota, Minneapolis, MN 55455, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, U.S. Gov't, Non-P.H.S., Research Support, Non-U.S. Gov't