The broad aim of the proposed research is to attack theoretical questions arising in various practical disease-related issues, especially in connection with linkage analysis (of putative disease loci to markers), ascertainment corrections (usually associated with disease data) and the physical mapping of gene loci using anchored clones.
Some specific aims of the proposed research are: (i) To continue work on the transmission distortion test (TDT) described elsewhere in this proposal. The TDT tests for linkage between marker and disease loci, and was developed to analyse data from presently or recently stratified populations. (ii) To continue research on the very difficult theory of ascertainment sampling where the data were collected by an ascertainment procedure on one variable (e.g. blood pressure) but the analysis considers a second, correlated, variable- (e.g. serum cholesterol level). (iii) To continue research, using computer simulations,. on the statistical properties of genome mapping using anchored clones, especially in cases where complexities such as hotspots make 'an analytical approach very difficult. (iv) To initiate research on statistical tests for comparing two or more populations-with respect to genetical characteristics (for example to compare the heterozygosity of two populations using restriction endonuclease data). (v) To initiate research on the question of assessing, when several loci contribute towards a disease, how much of the total (genetic) contribution is accounted for by each locus, and what the inactive effects between the loci on their contributions are.

Agency
National Institute of Health (NIH)
Institute
National Institute of General Medical Sciences (NIGMS)
Type
Research Project (R01)
Project #
5R01GM021135-24
Application #
2444454
Study Section
Genetics Study Section (GEN)
Project Start
1974-04-01
Project End
1998-06-30
Budget Start
1997-07-01
Budget End
1998-06-30
Support Year
24
Fiscal Year
1997
Total Cost
Indirect Cost
Name
University of Pennsylvania
Department
Biology
Type
Schools of Arts and Sciences
DUNS #
042250712
City
Philadelphia
State
PA
Country
United States
Zip Code
19104
Spielman, R S; Ewens, W J (1998) A sibship test for linkage in the presence of association: the sib transmission/disequilibrium test. Am J Hum Genet 62:450-8
Spielman, R S; Ewens, W J (1996) The TDT and other family-based tests for linkage disequilibrium and association. Am J Hum Genet 59:983-9
McGinnis, R E; Ewens, W J; Spielman, R S (1995) The TDT reveals linkage and linkage disequilibrium in a rare disease. Genet Epidemiol 12:637-40
Nolan, P M; Sollars, P J; Bohne, B A et al. (1995) Heterozygosity mapping of partially congenic lines: mapping of a semidominant neurological mutation, Wheels (Whl), on mouse chromosome 4. Genetics 140:245-54
Ewens, W J; Spielman, R S (1995) The transmission/disequilibrium test: history, subdivision, and admixture. Am J Hum Genet 57:455-64
Spielman, R S; McGinnis, R E; Ewens, W J (1993) Transmission test for linkage disequilibrium: the insulin gene region and insulin-dependent diabetes mellitus (IDDM). Am J Hum Genet 52:506-16
Tavare, S; Ewens, W J; Joyce, P (1989) Is knowing the age-order of alleles in a sample useful in testing for selective neutrality? Genetics 122:705-11
Ewens, W J; Hodge, S E; Ping, F H (1986) The effects of a known family-size distribution on the estimation of genetic parameters. Am J Hum Genet 38:555-66
Ewens, W J; Spielman, R S (1985) Statistical properties of maximum likelihood estimators for genetic parameters of HLA-linked diseases. Am J Hum Genet 37:1172-91