Brian Zebrick1, Teesit Teeramongkolgul2, Romain Nicot3, Michael J Horton4, Gwenael Raoul5, Joel Ferri6, Alexandre R Vieira7, James J Sciote8. 1. Resident, Department of Orthodontics, Temple University, Philadelphia, Pa. 2. Fellow, Department of Orthodontics, Temple University, Philadelphia, Pa. 3. Resident, Oral and Maxillofacial Department, Université Lille Nord de France, Lille, France. 4. Research assistant professor, Department of Orthodontics, Temple University, Philadelphia, Pa. 5. Professor, Department of Oral and Maxillofacial, Université Lille Nord de France, Lille, France; UDSL, Roger Salengro Hospital, CHU; and INSERM U 1008, Controlled Drug Delivery Systems and Biomaterials, Lille, France. 6. Professor and head, Department of Oral and Maxillofacial Surgery, Université Lille Nord de France, Lille, France; UDSL, Roger Salengro Hospital, CHU; and INSERM U 1008, Controlled Drug Delivery Systems and Biomaterials, Lille, France. 7. Associate professor, Department of Oral Biology, School of Dental Medicine, University of Pittsburgh, Pittsburgh, Pa. 8. Professor, Department of Orthodontics, Temple University, Philadelphia, Pa. Electronic address: jjs6@dental.temple.edu.
Abstract
INTRODUCTION: α-Actinins are myofibril anchor proteins that influence the contractile properties of skeletal muscles. ACTN2 is expressed in slow type I and fast type II fibers, whereas ACTN3 is expressed only in fast fibers. ACTN3 homozygosity for the 577X stop codon (ie, changing 577RR to 577XX, the R577X polymorphism) results in the absence of α-actinin-3 in about 18% of Europeans, diminishes fast contractile ability, enhances endurance performance, and reduces bone mass or bone mineral density. We have examined ACTN3 expression and genetic variation in the masseter muscle of orthognathic surgery patients to determine the genotype associations with malocclusion. METHODS: Clinical information, masseter muscle biopsies, and saliva samples were obtained from 60 subjects. Genotyping for ACTN3 single nucleotide polymorphisms, real-time polymerase chain reaction quantitation of muscle gene message, and muscle morphometric fiber type properties were compared to determine statistical differences between genotype and phenotype. RESULTS: Muscle mRNA expression level was significantly different for ACTN3 single nucleotide polymorphism genotypes (P <0.01). The frequency of ACTN3 genotypes was significantly different for the sagittal and vertical classifications of malocclusion, with the clearest association being elevated 577XX genotype in skeletal Class II malocclusion (P = 0.003). This genotype also resulted in significantly smaller diameters of fast type II fibers in masseter muscles (P = 0.002). CONCLUSION: ACTN3 577XX is overrepresented in subjects with skeletal Class II malocclusion, suggesting a biologic influence during bone growth. ACTN3 577XX is underrepresented in subjects with deepbite malocclusion, suggesting that muscle differences contribute to variations in vertical facial dimensions.
INTRODUCTION: α-Actinins are myofibril anchor proteins that influence the contractile properties of skeletal muscles. ACTN2 is expressed in slow type I and fast type II fibers, whereas ACTN3 is expressed only in fast fibers. ACTN3 homozygosity for the 577X stop codon (ie, changing 577RR to 577XX, the R577X polymorphism) results in the absence of α-actinin-3 in about 18% of Europeans, diminishes fast contractile ability, enhances endurance performance, and reduces bone mass or bone mineral density. We have examined ACTN3 expression and genetic variation in the masseter muscle of orthognathic surgery patients to determine the genotype associations with malocclusion. METHODS: Clinical information, masseter muscle biopsies, and saliva samples were obtained from 60 subjects. Genotyping for ACTN3 single nucleotide polymorphisms, real-time polymerase chain reaction quantitation of muscle gene message, and muscle morphometric fiber type properties were compared to determine statistical differences between genotype and phenotype. RESULTS: Muscle mRNA expression level was significantly different for ACTN3 single nucleotide polymorphism genotypes (P <0.01). The frequency of ACTN3 genotypes was significantly different for the sagittal and vertical classifications of malocclusion, with the clearest association being elevated 577XX genotype in skeletal Class II malocclusion (P = 0.003). This genotype also resulted in significantly smaller diameters of fast type II fibers in masseter muscles (P = 0.002). CONCLUSION:ACTN3 577XX is overrepresented in subjects with skeletal Class II malocclusion, suggesting a biologic influence during bone growth. ACTN3 577XX is underrepresented in subjects with deepbite malocclusion, suggesting that muscle differences contribute to variations in vertical facial dimensions.
Authors: S J Swoap; R B Hunter; E J Stevenson; H M Felton; N V Kansagra; J M Lang; K A Esser; S C Kandarian Journal: Am J Physiol Cell Physiol Date: 2000-10 Impact factor: 4.249
Authors: Theresa M Zucchero; Margaret E Cooper; Brion S Maher; Sandra Daack-Hirsch; Buena Nepomuceno; Lucilene Ribeiro; Diana Caprau; Kaare Christensen; Yasushi Suzuki; Junichiro Machida; Nagato Natsume; Koh-Ichiro Yoshiura; Alexandre R Vieira; Ieda M Orioli; Eduardo E Castilla; Lina Moreno; Mauricio Arcos-Burgos; Andrew C Lidral; L Leigh Field; You-e Liu; Ajit Ray; Toby H Goldstein; Rebecca E Schultz; Min Shi; Marla K Johnson; Shinji Kondo; Brian C Schutte; Mary L Marazita; Jeffrey C Murray Journal: N Engl J Med Date: 2004-08-19 Impact factor: 91.245
Authors: Nan Yang; Daniel G MacArthur; Jason P Gulbin; Allan G Hahn; Alan H Beggs; Simon Easteal; Kathryn North Journal: Am J Hum Genet Date: 2003-07-23 Impact factor: 11.025
Authors: Carlos Eduardo Palhares Machado; Marta Regina Pinheiro Flores; Laíse Nascimento Correia Lima; Rachel Lima Ribeiro Tinoco; Ademir Franco; Ana Cristina Barreto Bezerra; Martin Paul Evison; Marco Aurélio Guimarães Journal: PLoS One Date: 2017-07-07 Impact factor: 3.240