Search PubMed⌕ Search

Biomedical subjects

M C King

Publications and source records attributed to M C King.

At least 91 records · Page 5Linked to original sources
PubMed1993

High-density genetic map of the BRCA1 region of chromosome 17q12-q21.

To facilitate the positional cloning of the breast-ovarian cancer gene BRCA1, we constructed a high-density genetic map of the 8.3-cM interval between D17S250 and GIP on chromosome 17q12-q21. Markers were mapped by linkage in the CEPH and in extended kindreds in our breast cancer series. The map comprises 33 ordered polymorphisms, including 12 genes and 21 anonymous markers, yielding an average of one polymorphism every 250 kb. Twenty-five of the markers are PCR-based systems. The order of polymorphic genes and markers is cen-D17S250-D17S518-HER2-THRA1-RARA-D17S80 -KRT10-[D17S800-D17S857]-GAS- D17S856-EDH17B-D17S855-D17S859-D17S858-[++ +PPY-D17S78]-D17S183-EPB3-D17S579- D17S509-[D17S508-D17S190 = D17S810]-D17S791-[D17S181 = D17S806]-D17S797- HOX2B-GP3A-[D17S507 = GIP]-qter. BRCA1 lies in the middle of the interval, between THRA1 and D17S183. Markers from this map can be used to determine whether cancer is linked to BRCA1 in families, to evaluate whether tumors have lost heterozygosity at loci in the region, and to identify probes for characterizing chromosomal rearrangements from patients and from tumors.

Alleles↗
PubMed1993

Genetic variation among the Mapuche Indians from the Patagonian region of Argentina: mitochondrial DNA sequence variation and allele frequencies of several nuclear genes.

DNA samples from 60 Mapuche Indians, representing 39 maternal lineages, were genetically characterized for (1) nucleotide sequences of the mtDNA control region; (2) presence or absence of a nine base duplication in mtDNA region V; (3) HLA loci DRB1 and DQA1; (4) variation at three nuclear genes with short tandem repeats; and (5) variation at the polymorphic marker D2S44. The genetic profile of the Mapuche population was compared to other Amerinds and to worldwide populations. Two highly polymorphic portions of the mtDNA control region, comprising 650 nucleotides, were amplified by the polymerase chain reaction (PCR) and directly sequenced. The 39 maternal lineages were defined by two or three generation families identified by the Mapuches. These 39 lineages included 19 different mtDNA sequences that could be grouped into four classes. The same classes of sequences appear in other Amerinds from North, Central, and South American populations separated by thousands of miles, suggesting that the origin of the mtDNA patterns predates the migration to the Americas. The mtDNA sequence similarity between Amerind populations suggests that the migration throughout the Americas occurred rapidly relative to the mtDNA mutation rate. HLA DRB1 alleles 1602 and 1402 were frequent among the Mapuches. These alleles also occur at high frequency among other Amerinds in North and South America, but not among Spanish, Chinese or African-American populations. The high frequency of these alleles throughout the Americas, and their specificity to the Americas, supports the hypothesis that Mapuches and other Amerind groups are closely related.(ABSTRACT TRUNCATED AT 250 WORDS)

Alleles↗
PubMed1993

Violence and abuse of women: a perinatal health care issue.

This article discusses the perinatal health issue of abuse directed at pregnant women by their intimate partners. The incidence, prevalence, and severity of intimate violence during pregnancy are presented, as is a discussion of the possible health disruptions that can occur as a result of violence and abuse. Nursing interventions for abused pregnant women are presented within a framework of advocacy and empowerment. Strategies for primary prevention are outlined, and methods of secondary and tertiary intervention are discussed. The article concludes with a discussion of culturally relevant practice for abused women.

Cultural Characteristics↗
PubMed1993

Changing women's lives: the primary prevention of violence against women.

Significant numbers of women in the United States experience violence and abuse in their intimate relationships that compromise the health and safety of the women and their children. This article discusses the problem of violence against women and outlines strategies for responding to violence and abuse in the primary care setting. Nurses can play a vital role in the primary prevention of abuse by implementing abuse screening and education on the issue of violence against women. This article presents strategies for the primary prevention of abuse and guidelines for mobilizing support for women. Collective prevention strategies aimed at eliminating violence against women at the institutional, community, professional, and political level are highlighted.

Adult↗
PubMed1993

Woman abuse: educational strategies to change nursing practice.

Nurses and other health care providers are ideal persons to intervene with women who are experiencing violence and abuse in their intimate relationships. All women are not assessed for this health care problem because of lack of education on the part of their health care providers. This article presents principles and methods for the provision of education about women abuse to practicing nurses and students in graduate and undergraduate nursing programs. By redressing this lack of knowledge and skills, nurses will be empowered to provide clinical intervention and leadership in addressing this major health and social problems. Sample outlines and objectives are provided.

Adult↗
PubMed1993

THRA1 and D17S183 flank an interval of < 4 cM for the breast-ovarian cancer gene (BRCA1) on chromosome 17q21.

In order to pinpoint the locale of the gene for early-onset familial breast and ovarian cancer (BRCA1), polymorphisms were developed within the locus for thyroid hormone receptor alpha (THRA1) and for several anonymous sequences at chromosome 17q12-q21. The THRA1 polymorphism is a dinucleotide repeat with 10 alleles and heterozygosity.79. Gene mapping in extended families with inherited, early-onset breast and ovarian cancer indicates that BRCA1 is distal to THRA1 and proximal to D17S183 (SCG43), an interval of < 4 cM. This locale excludes HER2, THRA1, WNT3, HOX2, NGFR, PHB, COLIA1, NME1, and NME2 as candidates for BRCA1 but does not exclude RARA or EDH17B. Resolving the remaining recombination events in these families by new polymorphisms in the THRA1-D17S183 interval will facilitate positional cloning of the breast-ovarian cancer gene on chromosome 17q12-q21.

Adult↗
PubMed1992

The gene for an inherited form of deafness maps to chromosome 5q31.

Primary--i.e., nonsyndromal-postlingual deafness is inherited as an autosomal dominant phenotype in a large kindred in Costa Rica. Genetically susceptible individuals begin to lose hearing at low frequencies at about age 10 years, after language and speaking are learned. Deafness inevitably progresses by age 30 years to bilateral hearing loss of all frequencies. Intelligence, fertility, and life expectancy are normal. The family traces its ancestry to an affected founder born in Costa Rica in 1754. We have mapped the gene for deafness in this kindred to chromosome 5q31, between the markers IL9 and GRL, by linkage analysis involving 99 informative relatives.

Base Sequence↗
PubMed1992

Identifying individuals by sequencing mitochondrial DNA from teeth.

Mitochondrial DNA (mtDNA) was extracted from teeth stored from 3 months to 20 years, including teeth from the semi-skeletonized remains of a murder victim which had been buried for 10 months. Tooth donors and/or their maternal relatives provided blood or buccal cells, from which mtDNA was also extracted. Enzymatic amplification and direct sequencing of roughly 650 nucleotides from two highly polymorphic regions of mtDNA yielded identical sequences for each comparison of tooth and fresh DNA. Our results suggest that teeth provide an excellent source for high molecular weight mtDNA that can be valuable for extending the time in which decomposed human remains can be genetically identified.

Base Sequence↗
PubMed1992

Genetic risk factors for perinatally acquired HIV-1 infection.

This study evaluates genetic influence on susceptibility to perinatal HIV-1 infection among 106 Black infants from New York and San Francisco born to mothers infected with HIV-1. Genes tested by molecular techniques are HLA class II loci DRB1, DPB1 and DQA1; HLA class III loci complement C4A and C4B; alpha and beta interferons; and the constant region of the T-cell receptor beta chain. Of the 106 infants analysed, 54 are infected with HIV and 52 remain uninfected at age 15 months and older. Genotypes in the HLA region appear to influence risk of HIV infection. Specifically, infants with the amino acid sequence -asp-glu-ala-val- at DPB1 positions #84-87 are more likely to be infected (P = 0.001) and infants with the allele DQA1*0102 are less likely to be infected (P = 0.031). Combinations of these two risk factors show a strong dose response (P = 0.0005). HLA DPB1 and DQA1 may play a direct role in immune response associated with HIV-1 infection, or the critical region may be located between these two genes. Characterisation of other class II HLA genes in these infants will allow more precise determination of the role of HLA loci in susceptibility to HIV-1 infection.

Alleles↗
PubMed1992

The influence of social and political violence on the risk of pregnancy complications.

BACKGROUND: Events in Chile provided an opportunity to evaluate health effects associated with exposure to high levels of social and political violence. METHODS: Neighborhoods in Santiago, Chile, were mapped for occurrences of sociopolitical violence during 1985-86, such as bomb threats, military presence, undercover surveillance, and political demonstrations. Six health centers providing prenatal care were then chosen at random: three from "high-violence" and three from "low-violence" neighborhoods. The 161 healthy, pregnant women due to deliver between August 1 and September 7, 1986, who attended these health centers were interviewed twice about their living conditions. Pregnancy complications and labor/delivery information were subsequently obtained from clinic and hospital records. RESULTS: Women living in the high-violence neighborhoods were significantly more likely to experience pregnancy complications than women living in lower violence neighborhoods (OR = 5.0; 95% CI = 1.9-12.6; p less than 0.01). Residence in a high-violence neighborhood was the strongest risk factor observed; results persisted after controlling for several sets of potential confounders. CONCLUSION: Living in areas of high social and political violence increased the risk of pregnancy complications among otherwise healthy women.

Adult↗
PubMed1992

Heterogeneity analysis of breast cancer families by using age at onset as a covariate.

An extension of the usual mixture model of heterogeneity (two family types, one with and one without linkage) is proposed by introducing age at onset as a covariate. The extended model defines age-dependent penetrances where the exact parametrization of age-at-onset distributions depends on the given genotype and family type (linked or unlinked). This extension was applied to breast cancer families. We postulated that the mean age at onset in individuals affected by the linked gene was lower than the mean age at onset in all other affected individuals. Linkage heterogeneity for breast cancer families was detected at a significance level of .003.

Adult↗
PubMed1992

Linkage of familial breast cancer to chromosome 17q21 may not be restricted to early-onset disease.

Lod scores for linkage between familial breast and ovarian cancer and markers on chromosome 17q21 are more frequently positive among families with disease diagnosed at younger ages than they are among older-onset families, suggesting that linkage is restricted to early-onset disease. However, for late-onset cases, the relative probability of sporadic rather than inherited disease is higher than previously suggested. If this correction is made, then later-onset families are much less informative; linkage heterogeneity based on age at onset is no longer significant; and for the sample of families as a whole, linkage is significant at a recombination fraction since demonstrated to be close to the correct local. There is probably more than one gene for inherited breast cancer, but heterogeneity may not be due to age at disease onset.

Adult↗
PubMed1992

Closing in on a breast cancer gene on chromosome 17q.

Linkage of early-onset familial breast and ovarian cancer to 11 markers on chromosome 17q12-q21 defines an 8-cM region which is very likely to include the disease gene BRCA 1. The most closely linked marker is D17S579, a highly informative CA repeat polymorphism. D17S579 has no recombinants with inherited breast or ovarian cancer in 79 informative meioses in the seven families with early-onset disease (lod score 9.12 at zero recombination). There is no evidence for linkage heterogeneity in the families with early-onset disease. The proportion of older-onset breast cancer attributable to BRCA 1 is not yet determinable, because both inherited and sporadic cases occur in older-onset families.

Base Sequence↗
PubMed1991

Localization of the early-onset breast cancer gene.

In several susceptible families, it is clear that breast cancer is associated with a gene on band q21 of chromosome 17. On the basis of analogy, it seems probable that the rare germ-line gene is prototypical of a mutant form of a gene involved in the pathogenesis of the most common cancer in women. A major effort is now under way to sequence and clone this intriguing gene.

Breast Neoplasms↗