Somatic mutations in DNA mismatch repair genes have been observed in sporadic tumors as well as cell lines and xenografts derived from such tumors implicating genetic defects of mismatch repair genes in the development of such tumors. However, the proportion of sporadic tumors in which mismatch repair genes have been inactivated has not been determined accurately. We have analyzed 66 sporadic c...

We have examined the long arm of chromosome 17 in sporadic breast carcinomas for the loss of heterozygosity (LOH) at 18 polymorphic loci. At least three distinct regions could be identified by the frequency of LOH and confirmed by high density deletion maps of individual tumor DNAs. A proximal region affected by LOH is located in a 22-cM region defined by D17S73 and NME1 and thus is similar in ...

The partner and localizer of BRCA2 (PALB2) gene was recently identified as a BRCA2-interacting protein and subsequently shown to be a Fanconi anemia gene (FANCN). Disease-associated point mutations resulting in protein truncation have been found in BRCA1/2 mutation-negative breast cancer families identifying PALB2 as a susceptibility gene for breast cancer. Aberrant promoter hypermethylation is...

Various genetic alterations in ulcerative colitis (UC)-associated colorectal cancers (CRCs) have been reported. However, almost all studies have shown abnormalities of the known genes that have been demonstrated in sporadic CRCs. To identify novel genetic alterations, we selected unintentionally 35 microsatellite markers, and performed allelotype study in CRCs or dysplastic lesions from UC. Hig...

A seasonally dependent total neutral wind model obtained from experimental data is used to evaluate the diurnal variation of the vertical ion velocity in the E-region at a high-latitude location (Tromsø), for each season, in the presence of an electric field with a typical diurnal variation for quiet auroral days. The diurnal variation and spatial locations of the vertical convergence of ions a...

Genetic instability of microsatellite repeat sequences [microsatellite instability (MI)] is commonly seen in tumors associated with the hereditary nonpolyposis colorectal cancer syndrome and is a result of inactivating mutations in any of several genes involved in a particular pathway of DNA mismatch repair. Sporadic (i.e., nonhereditary) manifestations of several tumor types, including colorec...

Evidence for alteration of the FHIT gene in a significant fraction of breast carcinomas has been reported, in apparent concordance with loss of heterozygosity (LOH) at chromosome region 3p14.2 in breast cancer and benign proliferative breast disease. A significantly higher frequency of LOH at the FHIT locus was reported for BRCA2-/- tumors, possibly due to misrepaired double-strand breaks at th...

Immune disorders may play an important role in the pathogenesis of Parkinson's disease (PD). Recently, polymorphisms in the HLA-DR region have been found to be associated with sporadic PD in European ancestry populations. However, polymorphisms in the HLA complex are highly variable with ethnic and geographic origin. To explore the relationships between polymorphisms of the HLA-DR region and sp...