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S Narod

Publications and source records attributed to S Narod.

At least 55 records · Page 3Linked to original sources
PubMed1994

Epidermolytic palmoplantar keratoderma cosegregates with a keratin 9 mutation in a pedigree with breast and ovarian cancer.

Epidermolytic palmoplantar keratosis (EPPK) cosegregates with breast and ovarian cancers in a large French pedigree, raising the possibility that a single genetic mutation might cause these conditions and offering a potential lead to the identification of a hereditary breast/ovarian cancer gene. We have performed linkage analysis and show that the EPPK locus lies on the long arm of chromosome 17 near the type I keratin gene cluster and the proposed breast cancer gene (BRCA1). The type I keratin 9 gene has been partially sequenced in four affected individuals. A single base mutation within the rod domain of the protein cosegregates with EPPK in all affected individuals tested. Although inheritance of this mutation is likely responsible for EPPK, it is unlikely to be the cause of the breast and ovarian cancer.

Adolescent↗
PubMed1994

The gene for hereditary breast-ovarian cancer, BRCA1, maps distal to EDH17B2 in chromosome region 17q12-q21.

A gene for hereditary breast and ovarian cancer, BRCA1, has been mapped to chromosome 17q12-q21. This gene is responsible for cancer susceptibility in the majority of families with multiple cases of ovarian cancer and early-onset breast cancer. We report linkage results of a family with 10 cases of breast cancer and a single case of ovarian cancer. A recombinant event in this family places BRCA1 distal (telomeric) to the locus EDH17B2, which codes for the enzyme estradiol 17 beta-dehydrogenase II. This recombinant is based on the appearance of breast cancer in a 45 year old woman. Under our genetic model, we estimate the probability that this woman carries a BRCA1 mutation to be 94%. These data further reduce the region of assignment of BRCA1 on chromosome 17q12-q21 and should expedite positional cloning of this important gene.

Adult↗
PubMed1993

Detection of polymorphisms in the estradiol 17 beta-hydroxysteroid dehydrogenase II gene at the EDH17B2 locus on 17q11-q21.

The human estradiol 17 beta-hydroxysteroid dehydrogenase II (17 beta-HSD II) gene has been assigned by somatic cell hybridization to chromosome 17q11-q21, near the region of assignment of the gene BRCA1, which is involved in hereditary breast-ovarian cancer. The nucleotide sequence of 17 beta-HSD II was completely determined in four unrelated individuals. Direct sequencing of PCR fragments that span the complete 17 beta-HSD II gene revealed a total of 11 allelic variants which were due to single base substitutions. The presence of these variants was then studied in twenty six additional unrelated individuals. There were nine frequent and two rare polymorphisms. Seven of the 11 polymorphisms were in complete linkage disequilibrium. These polymorphisms in the 17 beta-HSD II gene provide markers that can be used for the genetic mapping of this locus, and may be used to establish whether 17 beta-HSD II is a candidate gene for hereditary breast-ovarian cancer.

17-Hydroxysteroid Dehydrogenases↗
PubMed1993

Germline deletion in a neurofibromatosis type 2 kindred inactivates the NF2 gene and a candidate meningioma locus.

Neurofibromatosis type 2 (NF2) is an autosomal dominant disease which predisposes to the development of schwannomas, meningiomas, ependymomas, and juvenile cataracts. The NF2 gene (NF2) has recently been isolated and maps to chromosome 22q12 between the loci D22S212 and D22S32. Deletion studies in sporadic and NF2 associated schwannomas and meningiomas, and the presence of inactivating mutations in NF2 in patients suggest that it acts as a tumor suppressor gene. A candidate meningioma gene (MEN) has also been isolated from the same interval. A new highly polymorphic (CA)n marker, D22S268, which maps very near to NF2, has allowed us to identify a kindred with three living affected individuals, where the disease is presumably caused by a large germline deletion. Fluorescence in situ hybridization and pulsed field gel electrophoresis confirm the presence of a 700kb deletion which includes the neurofilament heavy chain subunit gene locus (NEFH), D22S268, NF2 and the putative MEN gene. The absence of meningiomas in this pedigree raises doubts as to the existence of a separate MEN locus in this region. These results support the hypothesis that NF2 results from the inactivation of a tumor suppressor gene on chromosome 22q.

Cells, Cultured↗
PubMed1991

Counselling under genetic heterogeneity: a practical approach.

Hereditary diseases due to mutation at different gene loci may be indistinguishable phenotypically. In these situations genetic risk predictions using polymorphic markers may be hampered if an individual family is not sufficiently informative to permit it to be assigned to one or the other linkage group. To provide the most usefull estimates of risk, the probability of linkage to a particular chromosome region should be determined prior to calculating risk estimates using the marker system. The probability can be calculated directly using the lod score generated for the family. The individual carrier risk is then the average of the carrier risks determined for linkage to different genetic loci, weighted by the probability of linkage to each group. Several examples are provided.

Genetic Counseling↗
PubMed1991

[Genetics of neurofibromatosis: recent progress and prospects].

Two forms of neurofibromatosis are currently described. Von Reckinghausen Neurofibromatosis (NF 1) is the classic and common form, recently localised to chromosome 17. Neurofibromatosis type 2 (NF 2) or bilateral acoustic Neurofibromatosis, formerly the "central form" of von Reckinghausen disease, is characterized by multiple brain tumors, most often bilateral acoustic neuromas. The NF 2 mutation lies on the long arm of chromosome 22. The two forms predispose to benign or malignant familial tumors, derived from neural crest germ lines, such as Schwann cells. Rapid progress in the understanding of mechanisms underlying neurological tumor formation is expected in these inherited diseases. Molecular biology will allow the precise identification of genes responsible for the neurofibromatose syndromes. Practical applications, such as screening of individuals at risk for the disease will soon be available. Medical follow-up and genetic counselling should improve as a result of these advances.

Genes, Neurofibromatosis 1↗
PubMed1990

[Neuroblastoma in the Rhone-Alpes area: epidemiologic data].

An epidemiological study of neuroblastoma in the Rhône-Alpes area was carried out over a 5 year period. The aim was to set up a background for a screening program in order to increase the number of neuroblastoma diagnosed in children before age 1, and decrease or eliminate advanced stage neuroblastomas.

Adolescent↗
PubMed1986

Multiple sclerosis, latitude and dietary fat: is pork the missing link?

The relationship between prevalence rates of multiple sclerosis (MS) in several countries and the corresponding per capita consumption of fat, beef and pork was investigated. A significant correlation was obtained between prevalence of multiple sclerosis and fat intake (r = 0.63, p less than 0.01), total meat intake (r = 0.61, p less than 0.01) and pork consumption (r = 0.87, p less than 0.001). There was no significant correlation with beef consumption. The mechanism by which pork intake may increase the risk of developing MS is unknown and deserves further study.

Animals↗
PubMedDate not supplied

A supportive-expressive group intervention for women with a family history of breast cancer: results of a phase II study.

BACKGROUND: Evidence suggests that there are significant psychological and behavioural sequelae associated with having a family history of breast cancer (BC) which can interfere with comprehension of risk estimates. PURPOSE: The purpose of this study was to develop, standardize and do preliminary testing of a group intervention designed to address the emotional impact of having a family history of BC. METHODS: This study is a single-arm pilot design with pre- and post-measures of perceived risk, psychosocial distress, knowledge and screening practices. RESULTS: The primary study outcome measure of risk comprehension was significantly improved by 70%, according to our predetermined criteria for success. In addition, the most important secondary measures of psychosocial functioning, such as cancer-related distress (p=0.025), depression (p=0.05), anxiety (p=0.005) and unresolved grief (p=0.034) were significantly improved. CONCLUSION: The results of this initial pilot study are encouraging; however, further research is required, using a randomized controlled study design to evaluate the relative contribution of this intervention to the successful modification of risk comprehension, enhanced psychological functioning, and to promote optimal screening adherence.

Adaptation, Psychological↗
PubMedDate not supplied

Hereditary breast cancer and family cancer syndromes.

Hereditary breast cancer (HBC) shows extant clinical and genetic heterogeneity. Clinically one finds the onset of breast cancer at an early age, an excess of bilaterality, and patterns of multiple primary cancer such as combinations of breast and ovarian carcinoma in the hereditary breast-ovarian cancer (HBOC) syndrome. In addition to HBOC, one sees a variety of putative breast cancer-prone genotypes inclusive of hereditary site-specific breast cancer, and the Li-Fraumeni (SBLA) syndrome that is characterized by cancers involving all three germinal layers including sarcomas, brain tumors, leukemia, lymphoma, and adrenal cortical carcinoma in addition to often markedly early-onset breast cancer. Breast cancer is also associated with autosomal dominantly inherited Cowden's disease and autosomal recessively inherited ataxia-telangiectasia. Examples of pedigrees depicting clinical examples of these several HBC syndromes are presented in order to describe HBC's heterogeneity. The recent identification of the BRCA1 gene in early-onset hereditary site-specific breast cancer and the HBOC syndrome has led to new challenges for the genetic counselor. We review genetic counseling, which embraces surveillance and management recommendations that are responsive to the natural history of HBC and address the concept for future development of centers of expertise for HBC in the interest of improving cancer control.

Age of Onset↗