Effect of Genetic and Environmental Factors on Writing Development

ABSTRACT


Researchershaveidentiedsourcesofindividualdierencesinwritingacrossbeginninganddevelopingwriters. Theaimofthepresentstudywastofurtherclarifythesourcesofthisvariabilitybyinvestigatingtheextentto whichtherearedierencesingeneticandenvironmentalfactorsunderlyingtheassociationsbetweenlexical diversity,syntacticknowledge,andsemanticcohesionknowledgeinrelationtowriting.Dierenceswereexaminedacrosstwodevelopmentalphasesofwriting:beginning(i.e.,elementaryschool)anddeveloping(i.e., middleschool).Participantsincluded262twinpairs(Mage=10.88years)inelementaryschooland247twin pairs(Mage=13.21years)inmiddleschool.TwinsweredrawnfromtheFloridaTwinProjectonReading, Behavior,andEnvironment.Biometricmodelswereconductedseparatelyforsubgroupsdenedbyphaseof writingdevelopment.Resultsindicatedsignicantetiologicaldierencesinwritingcomponentsacrossthetwo phases,suchthateectsassociatedwithgenesandnon-sharedenvironmentweregreaterwhileeectsassociated withsharedenvironmentwerelowerindevelopingwritersascomparedtobeginningwriters.Furthermore, resultsshowedthatchild-specicenvironmentwasthelargestcontributortoindividualdierencesinwriting componentsandtheircovariationforbothbeginninganddevelopingwriters.Theseresultsimplythateven directinstructionaboutwritinginschoolsmaybehavingdierenteectsonchildrenbasedontheirunique experiences


Keywords: Writing, Etiology, Developmentaldierences, Twins