## Warren J Ewens, PhD

Professor of Genetics

Department: Genetics

Graduate Group Affiliations

Contact information

324 Leidy Laboratories

Philadelphia, PA 19104

Philadelphia, PA 19104

Office: 215 898.7109

Fax: 215 898.8780

Fax: 215 898.8780

Email:

wewens@sas.upenn.edu

wewens@sas.upenn.edu

Publications

Education:

PhD (Statistics)

Australian National University, 1963.

Permanent linkPhD (Statistics)

Australian National University, 1963.

### Description of Research Expertise

My research interests cover all areas of mathematical, statistical and theoretical genetics.A main area of interest is evolutionary population genetics, in particular statistical and mathematical aspects of the theory. Population genetics aims at elucidating the evolutionary process in Mendelian terms. Because of the quantitative nature of gene transmission, this is a highly mathematical subject. One specific field of interest is phylogenetic tree reconstruction: here the DNA sequences of various species are given, and from these it is desired to reconstruct a tree of evolution. Another field of interest is the statistical theory arising from the recognition of the stochastic, or random, aspect of gene replacement processes. This requires the use of Markov chain theory and also diffusion theory. A further area of interest in evolutionary genetics is in the complex multilocus theory arising when arbitrary epistatic interactions between gene loci are allowed.

A second main interest is the use of mathematical methods in human genetics, specifically in methods for mapping disease genes. A recent development made in conjunction with R. S. Spielman is the transmission/disequilibrium test: this test is frequently used for fine genetic linkage analysis. Other interests in this area include the resolution of the ascertainment sampling problem: this problem arises because of the non-random sampling frequently used to find the genetic properties of diseases, and requires the development of new statistical testing and estimation procedures. I have developed a method which, in a wide variety of cases, overcomes the problems involved in non-random sampling and provides a method of analysis whatever the ascertainment process of the data might be.

A final area of interest is computational biology. Especially with the accumulation of vast quantities of data for the human genome project, and of analogous projects for other species, computer and mathematical methods are needed for the storage, retrieval and analysis of DNA sequences.

### Selected Publications

**Ewens, W.J., S. Ogino, D. Leonard, H. Rennert, and R. Wilson**:

*Genetic risk assessment in carrier testing for spinal muscular atrophy*Am. J. Med. Genet. 110: 301-307, 2002.

**Ewens W.J.**:

*Population genetics*. Biological Statistical Genetics. R. Elston, J. Olson and L. Palmer (eds.). Wiley, New York, Page: 633-640, 2002.

**Ewens, W.J. and N. Kaplan**:

*Linkage analysis and coalescents*. Modern Developments in Theoretical Population Genetics. M. Slatkin and M. Veuille (eds.). Oxford University Press, Oxford, Page: 183-193, 2002.

**Ewens, W.J., J.A. Watts, M. Morley, J.T. Burdick, J.L. Fiori, R.S.Spielman, and V.G. Cheung**:

*Gene expression phenotype in carriers of recessive disease: ataxia telangiectasia*. Amer. J. Hum. Genet. 71: 791-800, 2002.

**Ewens, W.J. and G. R. Grant**:

*Statistical Methods in Bioinformatics*. Springer Verlag, New York, 2001.