title: Rapid automated landmarking for morphometric analysis of three-dimensional facial scans.
abstract: Automated phenotyping is essential for the creation of large, highly standardized datasets from anatomical imaging data. Such datasets can support large-scale studies of complex traits or clinical studies related to precision medicine or clinical trials. We have developed a method that generates three-dimensional landmark data that meet the requirements of standard geometric morphometric analyses. The method is robust and can be implemented without high-performance computing resources. We validated the method using both direct comparison to manual landmarking on the same individuals and also analyses of the variation patterns and outlier patterns in a large dataset of automated and manual landmark data. Direct comparison of manual and automated landmarks reveals that automated landmark data are less variable, but more highly integrated and reproducible. Automated data produce covariation structure that closely resembles that of manual landmarks. We further find that while our method does produce some landmarking errors, they tend to be readily detectable and can be fixed by adjusting parameters used in the registration and control-point steps. Data generated using the method described here have been successfully used to study the genomic architecture of facial shape in two different genome-wide association studies of facial shape.
authors.affiliation: Department of Mathematics, Florida State University, Tallahassee, FL, USA.
authors.forename: Mao
authors.initials: M
authors.lastname: Li
authors.affiliation: Human Medical Genetics and Genomics Program, University of Colorado School of Medicine, Aurora, CO, USA.
authors.forename: Joanne B
authors.initials: JB
authors.lastname: Cole
authors.affiliation: Department of Anatomy, Catholic University of Health and Allied Sciences, Mwanza, Tanzania.
authors.forename: Mange
authors.initials: M
authors.lastname: Manyama
authors.affiliation: Department of Anatomy and Cell Biology, McCaig Institute for Bone and Joint Health, and Alberta Children's Hospital Research Institute, University of Calgary, Calgary, AB, Canada.
authors.forename: Jacinda R
authors.initials: JR
authors.lastname: Larson
authors.affiliation: National Institutes of Health (NIDCR), Bethesda, MD, USA.
authors.forename: Denise K
authors.initials: DK
authors.lastname: Liberton
authors.affiliation: Human Medical Genetics and Genomics Program, University of Colorado School of Medicine, Aurora, CO, USA.
authors.forename: Sheri L
authors.initials: SL
authors.lastname: Riccardi
authors.affiliation: Human Medical Genetics and Genomics Program, University of Colorado School of Medicine, Aurora, CO, USA.
authors.forename: Tracey M
authors.initials: TM
authors.lastname: Ferrara
authors.affiliation: Department of Mathematical and Statistical Science, University of Colorado Denver, Denver, CO, USA.
authors.forename: Stephanie A
authors.initials: SA
authors.lastname: Santorico
authors.affiliation: Department of Radiology and Hotchkiss Brain Institute, University of Calgary, Calgary, AB, Canada.
authors.forename: Jordan J
authors.initials: JJ
authors.lastname: Bannister
authors.affiliation: Department of Radiology and Hotchkiss Brain Institute, University of Calgary, Calgary, AB, Canada.
authors.forename: Nils D
authors.initials: ND
authors.lastname: Forkert
authors.affiliation: Human Medical Genetics and Genomics Program, University of Colorado School of Medicine, Aurora, CO, USA.|Department of Pediatrics, University of Colorado School of Medicine, Aurora, CO, USA.
authors.forename: Richard A
authors.initials: RA
authors.lastname: Spritz
authors.affiliation: Department of Mathematics, Florida State University, Tallahassee, FL, USA.
authors.forename: Washington
authors.initials: W
authors.lastname: Mio
authors.affiliation: Department of Anatomy and Cell Biology, McCaig Institute for Bone and Joint Health, and Alberta Children's Hospital Research Institute, University of Calgary, Calgary, AB, Canada.
authors.forename: Benedikt
authors.initials: B
authors.lastname: Hallgrimsson
mesh_terms: D056667:Biometric Identification / Q000379:methods*; D005145:Face / Q000033:anatomy & histology*; D055106:Genome-Wide Association Study / Q000379:methods*; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D021621:Imaging, Three-Dimensional / Q000379:methods*
keywords: automated landmarking; automated phenotyping; face; facial imaging; human; morphometrics; phenomics; phenotyping; three-dimensional landmarks