title: Subclinical phenotypic expressions in heterozygous females of X-linked recessive bulbospinal neuronopathy.
abstract: Four of 8 definite heterozygous female carriers determined by PCR amplification of tandem CAG repeat of the AR gene, from 4 families of X-linked recessive bulbospinal neuronopathy (X-BSNP) showed extensive high amplitude motor unit potentials in examined muscles although all subjects were neurologically normal. Plasma creatine kinase, myoglobin, myosin light chain, lactate and pyruvate were all normal even in the carriers who showed EMG abnormalities. Muscle biopsy showed a type 2 fiber preponderance and possible very mild type 2 fiber grouping in a carrier with an EMG abnormality. These results suggest that a mutant AR gene may express subclinical phenotypic manifestations in a subpopulation of the heterozygous females of X-BSNP.
authors.affiliation: Fourth Department of Internal Medicine, Aichi Medical University, Japan.
authors.forename: G
authors.initials: G
authors.lastname: Sobue
authors.forename: M
authors.initials: M
authors.lastname: Doyu
authors.forename: T
authors.initials: T
authors.lastname: Kachi
authors.forename: T
authors.initials: T
authors.lastname: Yasuda
authors.forename: E
authors.initials: E
authors.lastname: Mukai
authors.forename: T
authors.initials: T
authors.lastname: Kumagai
authors.forename: T
authors.initials: T
authors.lastname: Mitsuma
mesh_terms: D000200:Action Potentials; D001483:Base Sequence; D001706:Biopsy; D004303:Dosage Compensation, Genetic; D004576:Electromyography; D005260:Female; D006579:Heterozygote; D006801:Humans; D008297:Male; D008969:Molecular Sequence Data; D016472:Motor Neuron Disease / Q000235:genetics* / Q000503:physiopathology; D009132:Muscles / Q000473:pathology; D009845:Oligospermia / Q000235:genetics; D010375:Pedigree; D010641:Phenotype; D011944:Receptors, Androgen / Q000235:genetics*; D012091:Repetitive Sequences, Nucleic Acid; D014960:X Chromosome
chemical_list: D011944:Receptors, Androgen