230 likes | 268 Views
Genetics of Diabetes and Its Complications: Layers of Complexity. Craig L. Hanis, Ph.D. Human Genetics Center The University of Texas Health Science Center at Houston. University of Pittsburgh October 23, 2001. A Brief History of the Genetics of Diabetes. Nightmare. Disequilibrium.
E N D
Genetics of Diabetes and Its Complications: Layers of Complexity Craig L. Hanis, Ph.D. Human Genetics Center The University of Texas Health Science Center at Houston University of Pittsburgh October 23, 2001
A Brief History of the Genetics of Diabetes Nightmare Disequilibrium Headache Linkage Interactions Heterogeneity Complexity
Genetics of Diabetes Complications Headaches from the Nightmares & Nightmares from the Headaches
Rising Interest in the Genetics of Diabetes and Its Complications
Complex Inheritance • Model Free Linkage Approaches • Affected Pairs • Concordant Sib Pairs • Discordant Sib Pairs • Association Based Mapping • Transmission Disequilibrium Testing • Parent - Offspring Trios (pairs) • Traditional Associations • SNP-based mapping
Fine Mapping • Ultimately a Search for Association • Criteria for selecting samples • Affected/Unaffected • Segregating/Non-segregating • Haplotype Determination • enhanced by pedigrees?
Candidate Genes to Functional Variation Biological Candidates Direct Sequencing Functional Studies Positional Candidates Expressional Candidates
Type 2 Diabetes Among Mexican Americans in Starr County, Texas Hanis et al. (1983). Am J Epidemiol 118:659-672
Narrowing the NIDDM1 Region on Chromosome 2 300 cM – 300+ million base pairs NIDDM1 maps near D2S140 5 – 10 million base pairs 150,000 base pairs Direct Sequencing of 65,000 base pairs
-1,2,3,4 UCSNP-22,23,24,25,26 UCSNP-43,44,45,46 UCSNP-49,50,51,52 UCSNP-27,28,29 UCSNP-36,37 UCSNP-38,40 UCSNP-65 UCSNP-33 UCSNP-31 UCSNP-59 UCSNP-60 UCSNP-62 UCSNP-19 UCSNP-48 UCSNP-58 UCSNP-47 UCSNP-30 UCSNP-63 UCSNP-32 UCSNP-55 UCSNP-54 UCSNP-39 UCSNP-41 UCSNP-35 UCSNP-34 UCSNP-56 UCSNP-42 UCSNP-53 UCSNP Organization of the NIDDM1 Region UCSNP-20 UCSNP-57 1 2 3 4 5 6 7 8 9 10 12 14 15 VNTR-1 VNTR-2 13 11 (49136) Calpain 10 GPR35
UCSNP-43,44,45,46 UCSNP-57 UCSNP-59 UCSNP-60 UCSNP-62 UCSNP-65 UCSNP-20 UCSNP-56 UCSNP-19 UCSNP-48 UCSNP-58 UCSNP-47 UCSNP-30 UCSNP-63 UCSNP-42 UCSNP-32 1 2 3 4 5 6 7 8 9 10 12 14 15 13 11 Organization of the 31kb Calpain 10 Gene Region Click for larger picture
Alternative Splicing of Calpain 10 Exon Domain I II III T 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Calpain 10a Protease 672 1 41 304 491 ATG TAA Calpain 10b 544 ATG ag TGA Calpain 10c 517 ATG TAA Calpain 10d 513 ATG TGA Calpain 10e 444 ATG TGA ag Calpain 10f 274 gt ATG TGA Calpain 10g 139 ATG TGA Calpain 10h 138 ATG TAA
OGTT Glucose Response by Genotype GG AG AA
Mouse Pancreatic Islets in the Presence of Calpain Inhibitors have an approximate 2-fold increased Insulin Secretory Response Sreenen et al. (2000). Diabetes 49 suppl 1:A62
120.00 120.00 120.00 100.00 100.00 100.00 80.00 80.00 80.00 Insulin 60.00 60.00 60.00 40.00 40.00 40.00 20.00 20.00 20.00 0.00 0.00 0.00 0 30 60 90 120 0 30 60 90 120 0 30 60 90 120 200.00 200.00 200.00 180.00 180.00 180.00 160.00 160.00 160.00 Glucose 140.00 140.00 140.00 120.00 120.00 120.00 100.00 100.00 100.00 80.00 80.00 80.00 0 30 60 90 120 0 30 60 90 120 0 30 60 90 120 Chicago - N = 32 Colorado - N = 44 Los Angeles - N = 8 120.00 120.00 100.00 100.00 80.00 80.00 Insulin 60.00 60.00 40.00 40.00 20.00 20.00 0.00 0.00 0 30 60 90 120 0 30 60 90 120 200.00 200.00 180.00 180.00 160.00 160.00 Glucose 140.00 140.00 120.00 120.00 100.00 100.00 80.00 80.00 0 30 60 90 120 0 30 60 St. Louis - N = 29 Utah - N = 38 Seattle - N = 29 Insulin and Glucose by Calpain 10 Genotype 120.00 100.00 80.00 60.00 40.00 20.00 0.00 0 30 60 90 120 200.00 180.00 160.00 140.00 120.00 100.00 80.00 0 30 60 90 120 90 120
FSIVGTT Insulin by Calpain 10 Genotype Insulin - FSIVGTT 160 140 120 100 Insulin (uU/mL) 80 60 40 20 Time (minutes) 0 0 20 40 60 80 100 120 140 160