ABSTRACT
Facioscapulohumeral muscular dystrophy (FSHD) is a genetic myopathy with a remarkable intra- and inter-familial clinical heterogeneity. This study reports the clinical and genetic analysis of 133 individuals from 71 unrelated Greek families based on a revised clinical severity score (rCSS) index which was developed for clinical assessment regarding the disease progression. A high ratio (31/62, 50%) of probands' family members was found to be asymptomatic or minimally affected gene carriers of a contracted 4q allele. Moreover, a notable clinical variability of FSHD is reported concerning the detection of an identical de novo 13 b EcoRI fragment in monozygotic twins, as well as indications of founder effect. This is the first survey that presents data of FSHD families from an East Mediterranean country supporting the speculation that the prevalence of disease might be significantly underestimated and that synergistic factors could play an essential role on the progression of the disease.
Subject(s)
Muscular Dystrophy, Facioscapulohumeral/diagnosis , Muscular Dystrophy, Facioscapulohumeral/genetics , Mutation/genetics , Phenotype , Adolescent , Adult , Aged , Aged, 80 and over , Child , Child, Preschool , Chromosomes, Human, Pair 4 , Deoxyribonuclease EcoRI , Female , Genetic Testing , Greece , Humans , Male , Middle Aged , Twins, Monozygotic/genetics , Young AdultABSTRACT
Studying the electrophysiological characteristics of the various types of Charcot-Marie-Tooth disease is important in the understanding of its pathophysiology. The purpose of this study was to identify the frequency of fibrillation potentials and positive sharp waves (FP/PWs) in HMSN I and II and, since they are indices of denervation, to elucidate whether they are correlated with the amplitude of compound muscle action potentials (CMAP). We reviewed the electrophysiological findings of 47 patients who have been studied in our hospital and found to suffer from Charcot-Marie-Tooth polyneuropathy. FP/PW were graded according to a 4-grade scale and the 38 m/sec criterion for motor conduction velocity (MCV) was used for distinction between HMSN I and II subgroups. Seventy percent of HMSN II patients and 81% of HMSN I patients showed fibrillation potentials in the upper or lower limbs. There was no difference in the frequency of FP/PW appearance between the two groups. In the HMSN II group the FP/PW grade correlated with CMAP amplitude in the upper limbs. In both groups there was no correlation between FP/PW grade and MCV. Our findings might indicate that in HMSN I there is a considerable axonal destruction that occurs concurrently with myelin loss.
Subject(s)
Action Potentials/physiology , Charcot-Marie-Tooth Disease/physiopathology , Hereditary Sensory and Motor Neuropathy/physiopathology , Muscle, Skeletal/innervation , Adolescent , Adult , Aged , Child , Electromyography , Female , Humans , Male , Middle Aged , Muscle, Skeletal/physiopathologyABSTRACT
An eight-member family is presented with two female members suffering from the juvenile form of acid maltase deficiency (AMD), the diagnosis confirmed by biochemical study of muscle. Biochemical leucocyte investigation revealed reduced a-glucosidase activity in both patients, a brother and the parents. Endocrinological study of the family disclosed reduced levels of thyroxine binding globulin (TBG) in the father and the three daughters. We consider the co-existence of AMD and TBG deficiency interesting, as thyroxine seems to play a role in the activation of acid maltase.
