J Med Genet. 2012 Jan 3;
Scionti I, Fabbri G, Fiorillo C, Ricci G, Greco F, D'Amico R, Termanini A, Vercelli L, Tomelleri G, Cao M, Santoro L, Percesepe A, Tupler R

BackgroundFacioscapulohumeral muscular dystrophy (FSHD) is considered an autosomal dominant disease with a prevalence of 1 in 20 000. Almost all patients with FSHD carry deletions of integral copies of tandem 3.3 kb repeats (D4Z4) located on chromosome 4q35. However, FSHD families have been reported in which individuals carrying a D4Z4-reduced allele remain asymptomatic. Recently, it has been proposed that the D4Z4-reduced allele is pathogenic only in association with the permissive haplotype, 4APAS.Methods and resultsThrough the Italian National Registry for FSHD (INRF), genotype-phenotype correlations were extensively studied in 11 non-consanguineous families in which two D4Z4-reduced alleles segregate. Overall, 68 subjects carrying D4Z4-reduced alleles were examined, including 15 compound heterozygotes. It was found that in four families the only FSHD-affected subject was the compound heterozygote for the D4Z4-reduced allele, and 52.6% of subjects carrying a single D4Z4-reduced 4A161PAS haplotype were non-penetrant carriers; moreover, the population frequency of the 4A161PAS haplotype associated with a D4Z4-reduced allele was found to be as high as 1.2%.ConclusionsThis study reveals a high frequency of compound heterozygotes in the Italian population and the presence of D4Z4-reduced alleles with the 4A161PAS pathogenic haplotype in the majority of non-penetrant subjects in FSHD families with compound heterozygosity. These data suggest that carriers of FSHD-sized alleles with 4A161PAS haplotype are more common in the general population than expected on the basis of FSHD prevalence. These findings challenge the notion that FSHD is a fully penetrant autosomal dominant disorder uniquely associated with the 4A161PAS haplotype, with relevant repercussions for genetic counselling and prenatal diagnosis.

Dev Cell. 2012 Jan 17; 22(1): 38-51
Geng LN, Yao Z, Snider L, Fong AP, Cech JN, Young JM, van der Maarel SM, Ruzzo WL, Gentleman RC, Tawil R, Tapscott SJ

Facioscapulohumeral dystrophy (FSHD) is one of the most common inherited muscular dystrophies. The causative gene remains controversial and the mechanism of pathophysiology unknown. Here we identify genes associated with germline and early stem cell development as targets of the DUX4 transcription factor, a leading candidate gene for FSHD. The genes regulated by DUX4 are reliably detected in FSHD muscle but not in controls, providing direct support for the model that misexpression of DUX4 is a causal factor for FSHD. Additionally, we show that DUX4 binds and activates LTR elements from a class of MaLR endogenous primate retrotransposons and suppresses the innate immune response to viral infection, at least in part through the activation of DEFB103, a human defensin that can inhibit muscle differentiation. These findings suggest specific mechanisms of FSHD pathology and identify candidate biomarkers for disease diagnosis and progression.

Brain Dev. 2011 Dec 26;
Mizuno T, Komaki H, Sasaki M, Takanoha S, Kuroda K, Kon K, Mamiya S, Yoshioka M, Yatabe K, Mikata T, Ishihara T, Nakajima T, Watanabe H, Konagaya M, Mitani M, Konishi T, Tokita Y, Fukuda K, Tatara K, Maruta K, Imamura S, Shimazaki R, Ishikawa K, Saito T, Shinno S

Although muscular dystrophy patients often have feeding difficulty and need long-term enteral nutrition, only a few reports have described gastrostomy feeding in these patients. This study was designed to evaluate the efficacy and tolerance of gastrostomy feeding in patients with muscular dystrophy. We performed a retrospective, multicenter study on 144 patients with muscular dystrophy who received gastrostomy feeding between 2007 and 2009 in 25 neuromuscular centers in Japan. There were 77 Duchenne muscular dystrophy (median age at gastrostomy placement 26years, range 13-47years), 40 myotonic dystrophy (median age 54.5years, range 13-70years), 11 Fukuyama congenital muscular dystrophy (median age 22years, range 13-29years), 5 limb girdle muscular dystrophy (median age 62years, range 43-78years), and 5 facioscapulohumeral muscular dystrophy (median age 52years, range 28-67years) patients. Many benefits including amelioration of malnutrition, swallowing difficulty and respiratory status were observed after the introduction of gastrostomy feeding. Especially in patients with Duchenne muscular dystrophy, mean body weight significantly increased after gastrostomy placement. Although most complications, which are commonly observed in other populations, were tolerable, respiratory failure and peritonitis were important concerns. These findings suggest that gastrostomy placement at an appropriate time is advisable in patients with muscular dystrophy.

Neuromuscul Disord. 2011 Dec 15;
Lemmers RJ, O'Shea S, Padberg GW, Lunt PW, van der Maarel SM

Contemp Clin Trials. 2012 Mar; 33(2): 302-311
Hilbert JE, Kissel JT, Luebbe EA, Martens WB, McDermott MP, Sanders DB, Tawil R, Thornton CA, Moxley RT,

INTRODUCTION: Registries are becoming increasingly important for rare diseases as experimental therapies develop. This report describes the methodology behind the National Registry of Myotonic Dystrophy (DM) and Facioscapulohumeral Muscular Dystrophy (FSHD) Patients and Family Members to facilitate the development of other rare disease registries. We also highlight data about the pathophysiology and select burdens of DM and FSHD reported at baseline and longitudinally. METHODS: The Registry consists of de-identified, patient reported information collected at baseline and annually and information from review of medical records. Investigators can use the Registry to analyze de-identified data and to facilitate recruitment into clinical studies. RESULTS: To date, the Registry has enrolled 1611 members, facilitated 24 studies, and collected data annually for up to 8years. Genetic test results were obtained in 56.2% of enrollees. Approximately one-third of members used assistive devices and another one-third reported psychological problems at baseline. Wheelchair use was reported for both short and long distances by 7.0% of DM and 18.1% of FSHD members. Approximately 60% of members reported their employment was affected by their disease. CONCLUSIONS: Strengths of the Registry include large sample sizes, stringent review of clinical and molecular data, annually updated information, and regular interactions between patients and investigators. Registry data provide new insights into the burdens of DM and FSHD, such as, psychological problems and reduced employment. Opportunities abound for investigators to utilize Registry resources to assess the impact of these and other burdens on health care costs, progression of symptoms, and quality of life.

Neuromuscul Disord. 2011 Dec 7;
Wang CH, Leung M, Liang WC, Hsieh TJ, Chen TH, Jong YJ

This study aimed to evaluate muscle involvement pattern and correlate the lesions on muscle imaging with clinical features and D4Z4 fragment size in 24 patients with facioscapulohumeral muscular dystrophy (ESHD). The grading of the muscle image detected by computed tomography (CT) was based on a four-point semi-quantitative visual scale. On muscle CT, the most affected muscle was trapezium, followed by hamstrings. CT image identified hamstrings involvement rather than shoulder-girdle in clinically asymptomatic subjects. CT image also showed that axial muscle was affected in one-third of patients which appeared even earlier than clinical manifestation. Strong correlations between CT findings, serum creatine kinase level and clinical severity scores were also found. Asymmetric involvement was more evident on CT image than it identified in manual muscle strength testing. Inverse correlation between CT grade and D4Z4 fragment size was clearly demonstrated. These findings suggest muscle CT will be helpful for the process of early intervention in FSHD, even in subjects in a preclinical status.

Clin Chim Acta. 2012 Feb 18; 413(3-4): 520-4
Zhang Y, Huang JJ, Wang ZQ, Wang N, Wu ZY

Muscle enzymes sometimes can provide clues for many similar neuromuscular disorders. However literatures that described and compared the muscle enzyme levels among these diseases are few. We described their changes in a group of Chinese patients.We reviewed creatine kinase (CK), lactate dehydrogenase (LDH), aspartate transaminase (AST) levels and CK/lDH in Chinese patients with Duchene/Becker muscular dystrophy (DMD/BMD), facioscapulohumeral muscular dystrophy (FSHD), limb-girdle muscular dystrophy (LGMD), polymyositis (PM), lipid storage myopathy (LSM), motor neuron disease (MND) and spinal muscular atrophy (SMA). The diagnosis of DMD/BMD, FSHD, LSM and SMA was confirmed by genetic analysis. Comparisons between groups were tested by One-Way ANOVA analysis and LSD test.CK: DMD/BMD>PM>LGMD>LSM>FSHD>MND>SMA. LDH and AST: DMD/BMD>LSM>PM>LGMD>FSHD>SMA>MND. For MND, logCK in PMA is the highest. For SMA, logCK value in type III is the highest. LDH disproportionately elevates in LSM and SMA.This investigation described muscle enzyme profiles in a large cohort of Chinese patients with neuromuscular diseases. Muscle enzyme values may have some implications for making decision when the diagnosis is hard.

J Genet Couns. 2011 Nov 23;
Yanoov-Sharav M, Leshinsky-Silver E, Cohen S, Vinkler C, Michelson M, Lerman-Sagie T, Ginzberg M, Sadeh M, Lev D

Facioscapulohumeral muscular dystrophy (FSHD), is a dominantly inherited, late onset, progressive disease. At present, no treatment or prevention of symptoms are available. There is considerable clinical variability, even within families. The gene whose defect causes FSHD has not been identified, but molecular diagnosis can be made by analyzing D4Z4 repeat length on chromosome 4q35. The results can support or rule out the clinical diagnosis of FSHD, but there are also "gray zone", non-conclusive results. During the years 2000-6, 66 individuals (including 7 asymptomatic individuals), were tested in our institute for D4Z4 repeat number. In 77% of the cases the results were conclusive: two thirds of them supported a diagnosis of FSHD while in a third this diagnosis was ruled out. In 23% the results were in the gray zone. Cognitive involvement was rare, occurring only when the D4Z4 repeat size was very small (<15 kb). Maximal utilization of the existing molecular test for FSHD demands detailed clinical and family pedigree information. We recommend that comprehensive genetic counseling always be given before and after molecular testing for FSHD, in addition to the neurological follow-up. Presymptomatic testing should only be offered when complete molecular evaluation can be offered, including 4qA and 4qB variant analysis.

Eur J Hum Genet. 2011 Nov 23;
Homma S, Chen JC, Rahimov F, Beermann ML, Hanger K, Bibat GM, Wagner KR, Kunkel LM, Emerson CP, Miller JB

To explore possible mechanisms of pathology in facioscapulohumeral muscular dystrophy (FSHD), we generated a novel library of myogenic cells composed of paired cultures derived from FSHD subjects and unaffected first-degree relatives. We prepared cells from biopsies of both biceps and deltoid muscles obtained from each of 10 FSHD and 9 unaffected donors. We used this new collection to determine how family background and disease affected patterns of growth and differentiation, expression of a panel of candidate, and muscle-specific genes, and responses to exogenous stressors. We found that FSHD and unaffected cells had, on average, indistinguishable patterns of differentiation, gene expression, and dose-response curves to staurosporine, paraquat, hydrogen peroxide, and glutathione depletion. Differentiated FSHD and unaffected cultures were both more sensitive to glutathione depletion than proliferating cultures, but showed similar responses to paraquat, staurosporine, and peroxide. For stress responses, the sample size was sufficient to detect a 10% change in effect at the observed variability with a power of >99%. In contrast, for each of these properties, we found significant differences among cells from different cohorts, and these differences were independent of disease status, gender, or muscle biopsied. Thus, though none of the properties we examined could be used to reliably distinguish between FSHD and unaffected cells, family of origin was an important contributor to gene-expression patterns and stressor responses in cultures of both FSHD and unaffected myogenic cells.European Journal of Human Genetics advance online publication, 23 November 2011; doi:10.1038/ejhg.2011.213.

PLoS One. 2011; 6(11): e27413
Pope BD, Tsumagari K, Battaglia D, Ryba T, Hiratani I, Ehrlich M, Gilbert DM

Facioscapulohumeral muscular dystrophy (FSHD) is linked to contraction of an array of tandem 3.3-kb repeats (D4Z4) at 4q35.2 from 11-100 copies to 1-10 copies. The extent to which D4Z4 contraction at 4q35.2 affects overall 4q35.2 chromatin organization remains unclear. Because DNA replication timing is highly predictive of long-range chromatin interactions, we generated genome-wide replication-timing profiles for FSHD and control myogenic precursor cells. We compared non-immortalized myoblasts from four FSHD patients and three control individuals to each other and to a variety of other human cell types. This study also represents the first genome-wide comparison of replication timing profiles in non-immortalized human cell cultures. Myoblasts from both control and FSHD individuals all shared a myoblast-specific replication profile. In contrast, male and female individuals were readily distinguished by monoallelic differences in replication timing at DXZ4 and other regions across the X chromosome affected by X inactivation. We conclude that replication timing is a robust cell-type specific feature that is unaffected by FSHD-related D4Z4 contraction.

Clin Neurol Neurosurg. 2011 Nov 11;
Pastorello E, Cao M, Trevisan CP

INTRODUCTION: FacioScapuloHumeral Muscular Dystrophy (FSHD), a disease linked to a heterozygous D4Z4 deletion on chromosome 4q35, typically starts with shoulder-girdle and facial muscle involvement. Atypical presentations have occasionally been reported, but their frequency has still not been defined. PATIENTS AND METHODS: We studied the occurrence rate of FSHD with atypical onset in 122 symptomatic subjects from 76 unrelated families with genetically confirmed FSHD. These 75 males and 47 females, with a mean age of 49 years (range: 11-85), had a mean EcoRI fragment of 25kb (range: 11-38). RESULTS: Typical shoulder-girdle or facial weakness at onset was reported by 88 patients (72%). Unusual presentations included: foot drop in 16 (13%) and proximal lower limb weakness in eight patients (7%). Two cases at onset manifested quite atypical, apparently non-FSHD-related syndromes: a 42-year-old woman presented with infantile epilepsy and a 41-year-old man with myoglobinuria. In the latter patient, DNA analysis detected a 4q35 deletion associated to an heterozygous CAPN3 mutation. CONCLUSION: FSHD presentation with foot drop or lower limb proximal weakness appeared to be more frequent than expected. This type of weakness at onset has to be considered premature, but still representative of disease-related muscle involvement. Quite atypical onset appears very rare and calls for further investigation on non-FSHD-related etiology.

PLoS One. 2011; 6(10): e26820
Vanderplanck C, Ansseau E, Charron S, Stricwant N, Tassin A, Laoudj-Chenivesse D, Wilton SD, Coppée F, Belayew A

Facioscapulohumeral muscular dystrophy (FSHD) is linked to deletions in 4q35 within the D4Z4 repeat array in which we identified the double homeobox 4 (DUX4) gene. We found stable DUX4 mRNAs only derived from the most distal D4Z4 unit and unexpectedly extended to the flanking pLAM region that provided an intron and a polyadenylation signal. DUX4 encodes a transcription factor expressed in FSHD but not control primary myoblasts or muscle biopsies. The DUX4 protein initiates a large transcription deregulation cascade leading to muscle atrophy and oxidative stress, which are FSHD key features.We now show that transfection of myoblasts with a DUX4 expression vector leads to atrophic myotube formation associated with the induction of E3 ubiquitin ligases (MuRF1 and Atrogin1/MAFbx) typical of muscle atrophy. DUX4 induces expression of downstream targets deregulated in FSHD such as mu-crystallin and TP53. We developed specific siRNAs and antisense oligonucleotides (AOs) targeting the DUX4 mRNA. Addition of these antisense agents to primary FSHD myoblast cultures suppressed DUX4 protein expression and affected expression of the above-mentioned markers.These results constitute a proof of concept for the development of therapeutic approaches for FSHD targeting DUX4 expression.