1 / 24

Genetics and Human variation

Genetics and Human variation. Nick Martin Queensland Institute of Medical Research High Schools lecture: April 4, 2006. Individual differences. Physical attributes (height, eye color) Disease susceptibility (asthma, anxiety) Behavior (intelligence, personality)

Download Presentation

Genetics and Human variation

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. Genetics and Human variation Nick Martin Queensland Institute of Medical Research High Schools lecture: April 4, 2006

  2. Individual differences • Physical attributes (height, eye color) • Disease susceptibility (asthma, anxiety) • Behavior (intelligence, personality) • Life outcomes (income, children)

  3. Genetic Epidemiology • Establishing the role of genes and environment in variation in disease and complex traits • Finding those genes

  4. 3 Stages of Genetic Mapping • Are there genes influencing this trait? • Genetic epidemiological studies • Where are those genes? • Linkage analysis • What are those genes? • Association analysis

  5. MZ and DZ twins: determining zygosity using ABI Profiler™ genotyping (8 STR markers + sex) Zygosity Determination • Identity at marker loci - except for rare mutation MZ DZ DZ

  6. Total mole count for MZ and DZ twins MZ twins - 153 pairs, r = 0.94 DZ twins - 199 pairs, r = 0.60 400 400 300 300 Twin 1 Twin 1 200 200 100 100 0 0 0 100 200 300 400 0 100 200 300 400 Twin 2 Twin 2

  7. ACE Model for twin data 1 MZ=1.0 / DZ=0.5 E C A A C E e c a a c e PT1 PT2

  8. Sources of variation in QCST results Non-shared environment Additive genetic Shared environment

  9. Are there common genetic and environmental factors influencing Verbal IQ, Performance IQ and QCST results? A1 A2 C1 .43 .66 .79 .48 .74 .41 VIQ PIQ QCST .34 .43 .53 E1 E2 E3

  10. 3 Stages of Genetic Mapping • Are there genes influencing this trait? • Epidemiological studies • Where are those genes? • Linkage analysis • What are those genes? • Association analysis

  11. Linkage analysis

  12. Genetics of asthma DPP10 GPRA EHF, ELF5 (11p13) FCER1B PHF11 ADAM33 1 9 10 11 12 13 21 22 X Y 2 14 15 16 17 18 19 20 3 4 5 6 7 8 Replicated regions @ p<0.01 (LOD>1.2) – Ober et al. (2000) Positionally cloned genes EHF and ELF5 (11p13) not replicated

  13. Linkage = Co-segregation A3A4 A1A2 A1A3 A2A4 A2A3 Marker allele A1 cosegregates with dominant disease A1A2 A1A4 A3A4 A3A2

  14. Linkage Markers…

  15. Number of Flat Moles by size

  16. Human OCA2 and eye colour Zhu et al., Twins Res 7:197-210 (2004)

  17. First genome-wide linkage scan for Intelligence Posthuma et al., AJHG, in press

  18. 3 Stages of Genetic Mapping • Are there genes influencing this trait? • Epidemiological studies • Where are those genes? • Linkage analysis • What are those genes? • Association analysis

  19. Comparison of Affymetrix 10k, 100k, 500k SNP chips

  20. First (unequivocal) positional cloning of a complex disease QTL !

  21. Discordant caudal duplication in MZ twins 3 4 5 6 7 11 8 9 10 1 2 LTR Axin CpG Island Emma Whitelaw, Suyinn Chong Department of Biochemistry University of Sydney 308 bp 181 bp Twin 1- unaffected < Twin 2 - affected > Controls [e.g.]

  22. What do you need? • Interest in • Genetics • Maths/statistics • Computing • The human condition • Joining the most exciting game in town

More Related