Gender	Female
E-mail	adele.mitchell@mssm.edu
Education and Training	Ph.D. , Johns Hopkins University School of Medicine
	M.S. , Johns Hopkins University School of Hygiene and Public Health
	B.S. , Wheaton College

Mailing address:
1425 Madison Ave, Box 1498

Education and Training	Ph.D. , Johns Hopkins University School of Medicine
	M.S. , Johns Hopkins University School of Hygiene and Public Health
	B.S. , Wheaton College

Genetics of Complex Disease

Our research group has two aims: 1) To identify genetic variants that are associated with susceptibility to Crohn's Disease (CD) or with response to treatment of CD,  2)  To develop novel statistical genetics methods and evaluate/improve existing methods for application to the study of complex disease.

Crohn's disease (CD), is an inflammatory bowel disease affecting both small and large intestines.  The etiology of CD is multifactorial, including genetic and environmental components.  The contribution of genetic factors to CD has been well documented with family and twin studies.  Before high-throughput microsatellite and single nucleotide polymorphism (SNP) genotyping technologies were available, statistical modeling of disease patterns in families indicated that the underlying genetics of CD was likely to be complex (i.e., multiple genes are likely to be involved). This has proven true; several variants have identified as risk factors, conferring a 1.2 to 3 fold increase in risk, or protective factors, associated with 30-50% reduction in risk of disease.

Currently, we are working to estimate the contribution of known CD risk variants to disease in our study population and we are performing a genome-wide association study of over 500,000 SNPs in CD patients and unrelated, unaffected individuals to identify additional variants contributing to CD susceptibility. 

In addition, we work collaboratively with faculty throughout the institution, on issues of study design and data analysis.  These collaborative projects span a broad range of phenotypes: from psychiatric disorders to intrauterine growth restriction, study designs: family and population-based designs, and analysis issues: gene/environment interaction, whole genome association, multiple testing, and candidate pathway analysis, for example.

Mitchell AA, Cutler DJ, Chakravarti A. On the probability that a novel variant is a disease-causing mutation. Genome Res 2005; 15: 960-966.

Mitchell AA, Cutler DJ, Chakravarti A, Zwick ME. Discrepancies in dbSNP confirmation rates and allele frequency distributions from varying genotyping error rates and patterns. Bioinformatics 2004; 20: 1022-1032.

Mitchell AA, Chakravarti A, Cutler DJ. Undetected genotyping errors cause apparent overtransmission of common alleles in the transmission/disequilibrium test. Am J Hum Genet 2003; 72: 598-610.

Karplus TM, Jeronimo SM, Chang H, Helms BK, Burns TL, Wilson ME, Mitchell AA, Pugh EW, Braz RF, Bezzera FL, Murray JC. Association between the tumor necrosis factor locus and the clinical outcome of Leishmania chagasi infection. Infect Immun 2002; 70: 6919-6925.