title: Blue cone monochromatism in a female due to skewed X-inactivation.
abstract: Blue cone monochromatism (BCM) is a rare cone dystrophy with recessive X-linked inheritance and therefore diagnosed in males whereas females are clinically unaffected. We present a female with clinically manifested BCM. The diagnosis was genetically verified with the identification of one single red-green OPN1LW/MW hybrid gene harboring a point mutation c.607C>G, p.Cys203Arg that associates with BCM and in addition a completely biased X-inactivation in DNA isolated from full blood and buccal mucosa. The present case illustrates that females may develop symptoms of recessive X-linked eye diseases in rare cases.
authors.affiliation: Department of Clinical Genetics, Aalborg University Hospital/Vejle Hospital, Vejle, Denmark. anja.lisbeth.frederiksen@slb.regionsyddanmark.dk
authors.forename: Anja L
authors.initials: AL
authors.lastname: Frederiksen
authors.forename: Morten
authors.initials: M
authors.lastname: Duno
authors.forename: Lotte G
authors.initials: LG
authors.lastname: Welinder
mesh_terms: D002675:Child, Preschool; D003119:Color Perception Tests; D003117:Color Vision Defects / Q000175:diagnosis / Q000235:genetics*; D004596:Electroretinography; D005260:Female; D006801:Humans; D008297:Male; D010375:Pedigree; D017354:Point Mutation; D016133:Polymerase Chain Reaction; D017299:Rod Opsins / Q000235:genetics*; D041623:Tomography, Optical Coherence; D014786:Vision Disorders / Q000235:genetics; D014792:Visual Acuity; D049951:X Chromosome Inactivation / Q000235:genetics*
chemical_list: D017299:Rod Opsins; C095855:long-wavelength opsin; C095854:middle-wavelength opsin