title: Congenital mirror movements: phenotypes associated with DCC and RAD51 mutations.
abstract: Congenital mirror movements (CMM) is a disorder characterized by unintentional mirroring in homologous motor systems of voluntary movements on the opposite side, usually affecting the distal upper extremities. Genetic analyses have revealed involvement of three genes (DCC, RAD51, and DNAL4). We sought to distinguish whether different phenotypes of CMM exist, and if so, whether they might map to different causative genes. We studied 14 individuals across five families with dominantly-inherited CMM. We used accelerometer gloves to analyse the fine detail of index finger tapping movements, and applied standard genetic methodology to analyse DNA samples. Two forms of mirroring were distinguished: 'actual' in which the mirroring followed precisely the movements of the voluntary hand, and 'fractionated' in which the mirroring was saccadic. We found that actual mirroring was characteristic of individuals in a family with a RAD51 mutation, and fractionated more characteristic of a family with a DCC mutation. These findings are suggestive of specific genotype-phenotype correlations in CMM. Three heterozygous individuals (one RAD51; two DCC) showed no apparent mirroring on visual inspection, although mirroring was detectable with the accelerometer gloves. Thus, subclinical mirroring may be present even when undetectable on clinical observation.
authors: Department of Psychology and fMRIOtago, University of Otago, Dunedin, New Zealand. Electronic address: lfranz@psy.otago.ac.nz.
authors: Elizabeth A
authors: EA
authors: Franz
authors: Department of Pathology, University of Otago, Dunedin, New Zealand.
authors: Rachel
authors: R
authors: Chiaroni-Clarke
authors: Department of Pathology, University of Otago, Dunedin, New Zealand.
authors: Stephanie
authors: S
authors: Woodrow
authors: Department of Anatomy, University of Otago, Dunedin, New Zealand.
authors: Kelly A
authors: KA
authors: Glendining
authors: Department of Anatomy, University of Otago, Dunedin, New Zealand.
authors: Christine L
authors: CL
authors: Jasoni
authors: Clinical Genetics Group, Department of Women's and Children's Health, University of Otago, Dunedin, New Zealand.
authors: Stephen P
authors: SP
authors: Robertson
authors: Clinical Genetics Group, Department of Women's and Children's Health, University of Otago, Dunedin, New Zealand.
authors: R J McKinlay
authors: RJM
authors: Gardner
authors: Department of Pathology, University of Otago, Dunedin, New Zealand.
authors: David
authors: D
authors: Markie
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D056444:Axonemal Dyneins / Q000235:genetics; D000075389:DCC Receptor; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009069:Movement Disorders / Q000235:genetics*; D010375:Pedigree; D010641:Phenotype; D051135:Rad51 Recombinase / Q000235:genetics*; D011956:Receptors, Cell Surface / Q000235:genetics*; D025521:Tumor Suppressor Proteins / Q000235:genetics*; D055815:Young Adult
chemical_list: D000075389:DCC Receptor; C501909:DCC protein, human; D011956:Receptors, Cell Surface; D025521:Tumor Suppressor Proteins; C495153:RAD51 protein, human; D051135:Rad51 Recombinase; D056444:Axonemal Dyneins; C000593273:DNAL4 protein, human
keywords: Bimanual movements; Congenital mirror movements; DCC; Genotype–phenotype correlations; Movement disorder; RAD51