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ThisisafinalreportfromDr.Kuehn.Hisprojectwastomap
andidentifythediseasegene(s)forprimaryangleclosure
glaucoma(PACG)inBassetHounds.Glaucomaisaplumb-
ingproblemwithintheeye.Visionlossandpainisdueto
increasedpressurewithintheeyebecauseofanormaldrain
thatisclogged(openangle)orduetoamalformeddrain
withsmallerdrainageholes(closedangle).Mostcanine
primary(inherited)glaucomaisclassifiedasclosedangle.

Dr.Kuehnstates“inadditiontounderstandinghowthis

diseasemightdevelop,wewerealsointerestedindeveloping
apredictivegenetictestthatmightenablebreedersto
identifythosedogsatlowrisktodevelopthisdiseaselater
inlife.WhileitinitiallyappearedthatPACGmightbea
geneticallyrelativelysimplediseaseourstudiessoon
determinedthatthisisnotthecase.Ourworkfocusedon
threegroupsofanimals:twogroupsofcloselyrelateddogs
fromtwodifferentkennelsandathirdgroupofunrelated
dogs,contributedbycommunityveterinaryophthalmologists.
Ourfindingscanbesummarizedasfollows:

1.AsignificantshareofPACGinBassetHoundsiscaused

bymutationsinthegeneNEB.

2.SomeBassetswithPACGdonothavemutationsin

thisgene,whichsuggeststhatatleastoneothergeneis
involvedinthesedogs.

3.Wealsoidentifiedtwogenetic“riskfactors.”Theseare

probablynotstrongenoughtocausePACGbythemselves
butcouldinfluencehowearlythediseasebeginsorhow
severethediseasewillbe.

Wehavealsobeguntodevelopasimplegenetictestand

willbemakingthisavailabletobreedersinthenearfuture.”

ItisexcitingnewsthatacandidategeneforPACGhas

beenfoundinhounds!WhatisthegeneNEBandwhatdoes
itdo?TheNEBgeneencodesaproteincallednebulin,which
isanimportantcomponentofskeletalmuscle.Musclethat
isdeficientinnebulinisweakerthannormalmuscle.Atthis
time,wedon’tknowwhymutationofnebulinmightaffect
pressurewithintheeye.Welookforwardtomoreresearch
newsfromtheKuehnlab.

Thisisamid-yearonereport.Inthisfirstphaseofthestudy,
theinvestigatorsplannedtocompletetestingof“200candi-
dateassistancedogs(CanineCompanionsforIndependence)
intheDogCognitionTestBattery(DCTB),aninstrument
designedtoassessawiderangeofproblemsolvingskillsin
dogs.Wewillthenconductexploratoryanalysestoidentify
associationsbetweenindividualdifferencesinthese
cognitivetasksandsubsequenttrainingoutcomes.”

Theresultsareveryinteresting.“Currently,95dogsthat

haveparticipatedintheDCTBhaveeithersuccessfully
completedtraining(N=63)orbeenreleasedfromtraining
forbehavioralproblems(N=32).Preliminaryanalyses
revealseveralcognitiveteststhatdifferbetweengraduate
andreleaseddogs.(1)Graduatedogsexhibitedstronger
lateralitybiases(handedness)inafirst-steppingtestthan

releaseddogs.Behavioralindicesoflateralityarebelieved
toreflectlateralizationinthebrainandmaycorrespond
toindividualdifferencesintemperamentandemotional
reactivity(Branson&Rogers,2006).(2)Graduatedogs
scoredloweronaninhibitorycontroltaskrequiringthedog
toinhibitaprepotentresponsetoreachforfoodonthe
othersideofatransparentbarrier.(3)Graduatedogsmade
eyecontactwithahumanforlongerperiodsthanreleased
dogswhenasocialgamewasinterrupted.(4)Releaseddogs
weremorelikelytodisobeyacommandtositorstaywhen
theexperimenterturnedherbacktothedogthanwhenthe
experimenterwaswatching.Althoughgraduatedogswere
alsoslightlymorepronetodisobeywhennotwatched,
thedifferencebetweenthewatchingandnotwatching
conditionswassignificantlylargerforreleaseddogs.”

Grant01995.UnderstandingtheFlexibilityandLimitations
ofHowDogsAcquireKnowledgeandUnderstanding:
ApplicationtoServiceDogEmotionalHealthandSelection.

DukeCanineCognitionCenter

Grant01594.IdentifyingtheGenesAssociatedwithGlaucoma.

Dr.MarkusKuehn,UniversityofIowa

PhotobyBobCohen