QTL mapping for phenotypes measured over time

and interactive graphics

Karl Broman

Biostatistics & Medical Informatics, University of Wisconsin – Madison

http://www.biostat.wisc.edu/~kbroman

Inbred mice

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Human vs mouse

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Gravitropism

Phenotype movie

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Recombinant inbred lines

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Data: 162 Ler × Cvi RIL

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Phenotypes

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LOD curves at 62 min

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LOD curves at 62 min

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Permutations

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Single-QTL analyses

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Phenotypes measured over time

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Results: SLOD & MLOD

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Multiple-QTL models

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Penalized LOD

Among additive QTL models, maximize

pLOD(γ) = LOD(γ) – T × |γ|

γ = a multiple-QTL model

|γ| = no. QTL in the model

T = significance threshold

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Penalized LOD

Among additive QTL models, maximize

pLODt(γ) = LODt(γ) – T × |γ|

γ = a multiple-QTL model

|γ| = no. QTL in the model

T = significance threshold

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Forward selection

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Forward selection

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Forward selection

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LOD profile

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Multiple-QTL analyses

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Penalized LOD, extended

Among additive QTL models, maximize

pSLOD(γ) = avet LODt(γ) – TS × |γ|

pMLOD(γ) = maxt LODt(γ) – TM × |γ|

γ = a multiple-QTL model

|γ| = no. QTL in the model

T = penalties

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Results: SLOD

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Summary

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Acknowledgments

Edgar Spalding Botany, UW-Madison
Candace Moore
Logan Johnson
Il-youp Kwak Statistics, UW-Madison
NIH: R01 GM074244

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