Official reprint from UpToDate®
www.uptodate.com ©2017 UpToDate, Inc. and/or its affiliates. All Rights Reserved.

Myotonic dystrophy: Etiology, clinical features, and diagnosis

Basil T Darras, MD
David A Chad, MD
Section Editors
Jeremy M Shefner, MD, PhD
Douglas R Nordli, Jr, MD
Deputy Editor
John F Dashe, MD, PhD


Myotonic dystrophy (DM) is a clinically and genetically heterogeneous disorder. There are two major forms:

DM1, for a century known as Steinert disease

DM2, recognized in 1994 as a milder version of DM1

These autosomal dominant conditions are among the most common forms of adult-onset muscular dystrophy. However, DM is more than simply a muscular dystrophy per se, since affected individuals may show cataracts, cardiac conduction abnormalities, infertility, and insulin resistance. Furthermore, there is a severe congenital form of DM1 with marked developmental disability.

One consequence of the multisystemic nature of this disorder is that individuals affected by DM1 or DM2 may first present to internists, cardiologists, ophthalmologists, endocrinologists, and pediatricians (in the case of DM1), before they see a neurologist.

To continue reading this article, you must log in with your personal, hospital, or group practice subscription. For more information on subscription options, click below on the option that best describes you:

Subscribers log in here

Literature review current through: Nov 2017. | This topic last updated: Jun 06, 2017.
The content on the UpToDate website is not intended nor recommended as a substitute for medical advice, diagnosis, or treatment. Always seek the advice of your own physician or other qualified health care professional regarding any medical questions or conditions. The use of this website is governed by the UpToDate Terms of Use ©2017 UpToDate, Inc.
  1. Brook JD, McCurrach ME, Harley HG, et al. Molecular basis of myotonic dystrophy: expansion of a trinucleotide (CTG) repeat at the 3' end of a transcript encoding a protein kinase family member. Cell 1992; 68:799.
  2. Buxton J, Shelbourne P, Davies J, et al. Detection of an unstable fragment of DNA specific to individuals with myotonic dystrophy. Nature 1992; 355:547.
  3. Fu YH, Pizzuti A, Fenwick RG Jr, et al. An unstable triplet repeat in a gene related to myotonic muscular dystrophy. Science 1992; 255:1256.
  4. Harley HG, Brook JD, Rundle SA, et al. Expansion of an unstable DNA region and phenotypic variation in myotonic dystrophy. Nature 1992; 355:545.
  5. Mahadevan M, Tsilfidis C, Sabourin L, et al. Myotonic dystrophy mutation: an unstable CTG repeat in the 3' untranslated region of the gene. Science 1992; 255:1253.
  6. Liquori CL, Ricker K, Moseley ML, et al. Myotonic dystrophy type 2 caused by a CCTG expansion in intron 1 of ZNF9. Science 2001; 293:864.
  7. Dalton JC, Ranum LPW, Day JW. Myotonic dystrophy type 2. GeneReviews. www.ncbi.nlm.nih.gov/books/NBK1466/ (Accessed on October 17, 2016).
  8. Hamshere MG, Harley H, Harper P, et al. Myotonic dystrophy: the correlation of (CTG) repeat length in leucocytes with age at onset is significant only for patients with small expansions. J Med Genet 1999; 36:59.
  9. Udd B, Krahe R. The myotonic dystrophies: molecular, clinical, and therapeutic challenges. Lancet Neurol 2012; 11:891.
  10. Puymirat J, Giguère Y, Mathieu J, Bouchard JP. Intergenerational contraction of the CTG repeats in 2 families with myotonic dystrophy type 1. Neurology 2009; 73:2126.
  11. Pearson CE, Nichol Edamura K, Cleary JD. Repeat instability: mechanisms of dynamic mutations. Nat Rev Genet 2005; 6:729.
  12. Ashizawa T, Dubel JR, Harati Y. Somatic instability of CTG repeat in myotonic dystrophy. Neurology 1993; 43:2674.
  13. Thornton CA, Johnson K, Moxley RT 3rd. Myotonic dystrophy patients have larger CTG expansions in skeletal muscle than in leukocytes. Ann Neurol 1994; 35:104.
  14. Morales F, Couto JM, Higham CF, et al. Somatic instability of the expanded CTG triplet repeat in myotonic dystrophy type 1 is a heritable quantitative trait and modifier of disease severity. Hum Mol Genet 2012; 21:3558.
  15. Turner C, Hilton-Jones D. Myotonic dystrophy: diagnosis, management and new therapies. Curr Opin Neurol 2014; 27:599.
  16. Day JW, Ricker K, Jacobsen JF, et al. Myotonic dystrophy type 2: molecular, diagnostic and clinical spectrum. Neurology 2003; 60:657.
  17. Thornton CA. Myotonic dystrophy. Neurol Clin 2014; 32:705.
  18. Cho DH, Tapscott SJ. Myotonic dystrophy: emerging mechanisms for DM1 and DM2. Biochim Biophys Acta 2007; 1772:195.
  19. Lee JE, Cooper TA. Pathogenic mechanisms of myotonic dystrophy. Biochem Soc Trans 2009; 37:1281.
  20. Kino Y, Washizu C, Oma Y, et al. MBNL and CELF proteins regulate alternative splicing of the skeletal muscle chloride channel CLCN1. Nucleic Acids Res 2009; 37:6477.
  21. Cooper TA. A reversal of misfortune for myotonic dystrophy? N Engl J Med 2006; 355:1825.
  22. Fugier C, Klein AF, Hammer C, et al. Misregulated alternative splicing of BIN1 is associated with T tubule alterations and muscle weakness in myotonic dystrophy. Nat Med 2011; 17:720.
  23. Charlet-B N, Savkur RS, Singh G, et al. Loss of the muscle-specific chloride channel in type 1 myotonic dystrophy due to misregulated alternative splicing. Mol Cell 2002; 10:45.
  24. Savkur RS, Philips AV, Cooper TA. Aberrant regulation of insulin receptor alternative splicing is associated with insulin resistance in myotonic dystrophy. Nat Genet 2001; 29:40.
  25. Philips AV, Timchenko LT, Cooper TA. Disruption of splicing regulated by a CUG-binding protein in myotonic dystrophy. Science 1998; 280:737.
  26. Berg J, Jiang H, Thornton CA, Cannon SC. Truncated ClC-1 mRNA in myotonic dystrophy exerts a dominant-negative effect on the Cl current. Neurology 2004; 63:2371.
  27. Wheeler TM, Lueck JD, Swanson MS, et al. Correction of ClC-1 splicing eliminates chloride channelopathy and myotonia in mouse models of myotonic dystrophy. J Clin Invest 2007; 117:3952.
  28. Yadava RS, Frenzel-McCardell CD, Yu Q, et al. RNA toxicity in myotonic muscular dystrophy induces NKX2-5 expression. Nat Genet 2008; 40:61.
  29. Nakamori M, Kimura T, Kubota T, et al. Aberrantly spliced alpha-dystrobrevin alters alpha-syntrophin binding in myotonic dystrophy type 1. Neurology 2008; 70:677.
  30. Magee A, Nevin NC. The epidemiology of myotonic dystrophy in Northern Ireland. Community Genet 1999; 2:179.
  31. Siciliano G, Manca M, Gennarelli M, et al. Epidemiology of myotonic dystrophy in Italy: re-apprisal after genetic diagnosis. Clin Genet 2001; 59:344.
  32. Norwood FL, Harling C, Chinnery PF, et al. Prevalence of genetic muscle disease in Northern England: in-depth analysis of a muscle clinic population. Brain 2009; 132:3175.
  33. Yotova V, Labuda D, Zietkiewicz E, et al. Anatomy of a founder effect: myotonic dystrophy in Northeastern Quebec. Hum Genet 2005; 117:177.
  34. López de Munain A, Blanco A, Emparanza JI, et al. Prevalence of myotonic dystrophy in Guipúzcoa (Basque Country, Spain). Neurology 1993; 43:1573.
  35. Lotz BP, van der Meyden CH. Myotonic dystrophy. Part I. A genealogical study in the northern Transvaal. S Afr Med J 1985; 67:812.
  36. Ashizawa T, Epstein HF. Ethnic distribution of myotonic dystrophy gene. Lancet 1991; 338:642.
  37. Hsiao KM, Chen SS, Li SY, et al. Epidemiological and genetic studies of myotonic dystrophy type 1 in Taiwan. Neuroepidemiology 2003; 22:283.
  38. Goldman A, Ramsay M, Jenkins T. Ethnicity and myotonic dystrophy: a possible explanation for its absence in sub-Saharan Africa. Ann Hum Genet 1996; 60:57.
  39. Suominen T, Bachinski LL, Auvinen S, et al. Population frequency of myotonic dystrophy: higher than expected frequency of myotonic dystrophy type 2 (DM2) mutation in Finland. Eur J Hum Genet 2011; 19:776.
  40. Udd B, Meola G, Krahe R, et al. 140th ENMC International Workshop: Myotonic Dystrophy DM2/PROMM and other myotonic dystrophies with guidelines on management. Neuromuscul Disord 2006; 16:403.
  41. Arsenault ME, Prévost C, Lescault A, et al. Clinical characteristics of myotonic dystrophy type 1 patients with small CTG expansions. Neurology 2006; 66:1248.
  42. Wesström G, Bensch J, Schollin J. Congenital myotonic dystrophy. Incidence, clinical aspects and early prognosis. Acta Paediatr Scand 1986; 75:849.
  43. González de Dios J, Martínez Frías ML, Egües Jimeno J, et al. [Epidemiological study of Steinert's congenital myotonic dystrophy: dysmorphological characteristics]. An Esp Pediatr 1999; 51:389.
  44. Darin N, Tulinius M. Neuromuscular disorders in childhood: a descriptive epidemiological study from western Sweden. Neuromuscul Disord 2000; 10:1.
  45. Campbell C, Levin S, Siu VM, et al. Congenital myotonic dystrophy: Canadian population-based surveillance study. J Pediatr 2013; 163:120.
  46. Zaki M, Boyd PA, Impey L, et al. Congenital myotonic dystrophy: prenatal ultrasound findings and pregnancy outcome. Ultrasound Obstet Gynecol 2007; 29:284.
  47. Volpe JJ. Neuromuscular disorders: Muscle involvement and restricted disorders. In: Neurology of the Newborn, 5th ed, Saunders Elsevier, Philadephia 2008. p.801.
  48. Pearse RG, Höweler CJ. Neonatal form of dystrophia myotonica. Five cases in preterm babies and a review of earlier reports. Arch Dis Child 1979; 54:331.
  49. Shore RN, MacLachlan TB. Pregnancy with myotonic dystrophy: course, complications and management. Obstet Gynecol 1971; 38:448.
  50. Dunn LJ, Dierker LI. Recurrent hydramnios in association with myotonia dystrophica. Obstet Gynecol 1973; 42:104.
  51. Moosa A. The feeding difficulty in infantile myotonic dystrophy. Dev Med Child Neurol 1974; 16:824.
  52. Hageman AT, Gabreëls FJ, Liem KD, et al. Congenital myotonic dystrophy; a report on thirteen cases and a review of the literature. J Neurol Sci 1993; 115:95.
  53. Sarnat HB, O'Connor T, Byrne PA. Clinical effects of myotonic dystrophy on pregnancy and the neonate. Arch Neurol 1976; 33:459.
  54. Igarashi H, Momoi MY, Yamagata T, et al. Hypertrophic cardiomyopathy in congenital myotonic dystrophy. Pediatr Neurol 1998; 18:366.
  55. Roig M, Balliu PR, Navarro C, et al. Presentation, clinical course, and outcome of the congenital form of myotonic dystrophy. Pediatr Neurol 1994; 11:208.
  56. Modoni A, Silvestri G, Pomponi MG, et al. Characterization of the pattern of cognitive impairment in myotonic dystrophy type 1. Arch Neurol 2004; 61:1943.
  57. Bassez G, Lazarus A, Desguerre I, et al. Severe cardiac arrhythmias in young patients with myotonic dystrophy type 1. Neurology 2004; 63:1939.
  58. Redman JB, Fenwick RG Jr, Fu YH, et al. Relationship between parental trinucleotide GCT repeat length and severity of myotonic dystrophy in offspring. JAMA 1993; 269:1960.
  59. Tsilfidis C, MacKenzie AE, Mettler G, et al. Correlation between CTG trinucleotide repeat length and frequency of severe congenital myotonic dystrophy. Nat Genet 1992; 1:192.
  60. De Temmerman N, Sermon K, Seneca S, et al. Intergenerational instability of the expanded CTG repeat in the DMPK gene: studies in human gametes and preimplantation embryos. Am J Hum Genet 2004; 75:325.
  61. Nakagawa M, Yamada H, Higuchi I, et al. A case of paternally inherited congenital myotonic dystrophy. J Med Genet 1994; 31:397.
  62. Ohya K, Tachi N, Chiba S, et al. Congenital myotonic dystrophy transmitted from an asymptomatic father with a DM-specific gene. Neurology 1994; 44:1958.
  63. Tachi N, Ohya K, Yamagata H, et al. Haplotype analysis of congenital myotonic dystrophy patients from asymptomatic DM father. Pediatr Neurol 1997; 16:315.
  64. de Die-Smulders CE, Smeets HJ, Loots W, et al. Paternal transmission of congenital myotonic dystrophy. J Med Genet 1997; 34:930.
  65. Tanaka Y, Suzuki Y, Shimozawa N, et al. Congenital myotonic dystrophy: report of paternal transmission. Brain Dev 2000; 22:132.
  66. Harley HG, Rundle SA, MacMillan JC, et al. Size of the unstable CTG repeat sequence in relation to phenotype and parental transmission in myotonic dystrophy. Am J Hum Genet 1993; 52:1164.
  67. Zeesman S, Carson N, Whelan DT. Paternal transmission of the congenital form of myotonic dystrophy type 1: a new case and review of the literature. Am J Med Genet 2002; 107:222.
  68. Ekström AB, Hakenäs-Plate L, Tulinius M, Wentz E. Cognition and adaptive skills in myotonic dystrophy type 1: a study of 55 individuals with congenital and childhood forms. Dev Med Child Neurol 2009; 51:982.
  69. Douniol M, Jacquette A, Cohen D, et al. Psychiatric and cognitive phenotype of childhood myotonic dystrophy type 1. Dev Med Child Neurol 2012; 54:905.
  70. Angeard N, Jacquette A, Gargiulo M, et al. A new window on neurocognitive dysfunction in the childhood form of myotonic dystrophy type 1 (DM1). Neuromuscul Disord 2011; 21:468.
  71. Echenne B, Rideau A, Roubertie A, et al. Myotonic dystrophy type I in childhood Long-term evolution in patients surviving the neonatal period. Eur J Paediatr Neurol 2008; 12:210.
  72. Ho G, Cardamone M, Farrar M. Congenital and childhood myotonic dystrophy: Current aspects of disease and future directions. World J Clin Pediatr 2015; 4:66.
  73. Bhakta D, Lowe MR, Groh WJ. Prevalence of structural cardiac abnormalities in patients with myotonic dystrophy type I. Am Heart J 2004; 147:224.
  74. Avaria M, Patterson V. Myotonic dystrophy: relative sensitivity of symptoms signs and abnormal investigations. Ulster Med J 1994; 63:151.
  75. Bird TD. Myotonic dystrophy type 1. GeneReviews. www.ncbi.nlm.nih.gov/books/NBK1165/ (Accessed on October 18, 2016).
  76. Whittaker RG, Ferenczi E, Hilton-Jones D. Myotonic dystrophy: practical issues relating to assessment of strength. J Neurol Neurosurg Psychiatry 2006; 77:1282.
  77. Bouchard JP, Cossette L, Bassez G, Puymirat J. Natural history of skeletal muscle involvement in myotonic dystrophy type 1: a retrospective study in 204 cases. J Neurol 2015; 262:285.
  78. Mathieu J, Boivin H, Richards CL. Quantitative motor assessment in myotonic dystrophy. Can J Neurol Sci 2003; 30:129.
  79. Wiles CM, Busse ME, Sampson CM, et al. Falls and stumbles in myotonic dystrophy. J Neurol Neurosurg Psychiatry 2006; 77:393.
  80. Meola G, Moxley RT 3rd. Myotonic dystrophy type 2 and related myotonic disorders. J Neurol 2004; 251:1173.
  81. Ricker K, Koch MC, Lehmann-Horn F, et al. Proximal myotonic myopathy: a new dominant disorder with myotonia, muscle weakness, and cataracts. Neurology 1994; 44:1448.
  82. Udd B, Krahe R, Wallgren-Pettersson C, et al. Proximal myotonic dystrophy--a family with autosomal dominant muscular dystrophy, cataracts, hearing loss and hypogonadism: heterogeneity of proximal myotonic syndromes? Neuromuscul Disord 1997; 7:217.
  83. Papadimas GK, Kekou K, Papadopoulos C, et al. Phenotypic variability and molecular genetics in proximal myotonic myopathy. Muscle Nerve 2015; 51:686.
  84. Milone M, Batish SD, Daube JR. Myotonic dystrophy type 2 with focal asymmetric muscle weakness and no electrical myotonia. Muscle Nerve 2009; 39:383.
  85. Machuca-Tzili L, Brook D, Hilton-Jones D. Clinical and molecular aspects of the myotonic dystrophies: a review. Muscle Nerve 2005; 32:1.
  86. Suokas KI, Haanpää M, Kautiainen H, et al. Pain in patients with myotonic dystrophy type 2: a postal survey in Finland. Muscle Nerve 2012; 45:70.
  87. Heatwole C, Johnson N, Bode R, et al. Patient-Reported Impact of Symptoms in Myotonic Dystrophy Type 2 (PRISM-2). Neurology 2015; 85:2136.
  88. George A, Schneider-Gold C, Zier S, et al. Musculoskeletal pain in patients with myotonic dystrophy type 2. Arch Neurol 2004; 61:1938.
  89. Auvinen S, Suominen T, Hannonen P, et al. Myotonic dystrophy type 2 found in two of sixty-three persons diagnosed as having fibromyalgia. Arthritis Rheum 2008; 58:3627.
  90. Lund M, Diaz LJ, Ranthe MF, et al. Cardiac involvement in myotonic dystrophy: a nationwide cohort study. Eur Heart J 2014; 35:2158.
  91. Fragola PV, Luzi M, Calò L, et al. Cardiac involvement in myotonic dystrophy. Am J Cardiol 1994; 74:1070.
  92. Florek RC, Triffon DW, Mann DE, et al. Electrocardiographic abnormalities in patients with myotonic dystrophy. West J Med 1990; 153:24.
  93. Hawley RJ, Milner MR, Gottdiener JS, Cohen A. Myotonic heart disease: a clinical follow-up. Neurology 1991; 41:259.
  94. Melacini P, Buja G, Fasoli G, et al. The natural history of cardiac involvement in myotonic dystrophy: an eight-year follow-up in 17 patients. Clin Cardiol 1988; 11:231.
  95. Schoser BG, Ricker K, Schneider-Gold C, et al. Sudden cardiac death in myotonic dystrophy type 2. Neurology 2004; 63:2402.
  96. Groh WJ, Groh MR, Saha C, et al. Electrocardiographic abnormalities and sudden death in myotonic dystrophy type 1. N Engl J Med 2008; 358:2688.
  97. Phillips MF, Harper PS. Cardiac disease in myotonic dystrophy. Cardiovasc Res 1997; 33:13.
  98. Johnson NE, Abbott D, Cannon-Albright LA. Relative risks for comorbidities associated with myotonic dystrophy: A population-based analysis. Muscle Nerve 2015; 52:659.
  99. Wahbi K, Meune C, Bécane HM, et al. Left ventricular dysfunction and cardiac arrhythmias are frequent in type 2 myotonic dystrophy: a case control study. Neuromuscul Disord 2009; 19:468.
  100. Bogaard JM, van der Meché FG, Hendriks I, Ververs C. Pulmonary function and resting breathing pattern in myotonic dystrophy. Lung 1992; 170:143.
  101. Klompe L, Lancé M, van der Woerd D, et al. Anaesthesiological and ventilatory precautions during cardiac surgery in Steinert's disease. J Card Surg 2007; 22:74.
  102. Culebras A. Sleep and neuromuscular disorders. Neurol Clin 2005; 23:1209.
  103. Ho G, Widger J, Cardamone M, Farrar MA. Quality of life and excessive daytime sleepiness in children and adolescents with myotonic dystrophy type 1. Sleep Med 2017; 32:92.
  104. Laberge L, Gagnon C, Dauvilliers Y. Daytime sleepiness and myotonic dystrophy. Curr Neurol Neurosci Rep 2013; 13:340.
  105. Ono S, Takahashi K, Jinnai K, et al. Loss of serotonin-containing neurons in the raphe of patients with myotonic dystrophy: a quantitative immunohistochemical study and relation to hypersomnia. Neurology 1998; 50:535.
  106. Laberge L, Bégin P, Montplaisir J, Mathieu J. Sleep complaints in patients with myotonic dystrophy. J Sleep Res 2004; 13:95.
  107. Heatwole C, Bode R, Johnson N, et al. Patient-reported impact of symptoms in myotonic dystrophy type 1 (PRISM-1). Neurology 2012; 79:348.
  108. Tieleman AA, Knoop H, van de Logt AE, et al. Poor sleep quality and fatigue but no excessive daytime sleepiness in myotonic dystrophy type 2. J Neurol Neurosurg Psychiatry 2010; 81:963.
  109. Vazquez JA, Pinies JA, Martul P, et al. Hypothalamic-pituitary-testicular function in 70 patients with myotonic dystrophy. J Endocrinol Invest 1990; 13:375.
  110. Ørngreen MC, Arlien-Søborg P, Duno M, et al. Endocrine function in 97 patients with myotonic dystrophy type 1. J Neurol 2012; 259:912.
  111. Peric S, Nisic T, Milicev M, et al. Hypogonadism and erectile dysfunction in myotonic dystrophy type 1. Acta Myol 2013; 32:106.
  112. Rönnblom A, Forsberg H, Danielsson A. Gastrointestinal symptoms in myotonic dystrophy. Scand J Gastroenterol 1996; 31:654.
  113. Bellini M, Biagi S, Stasi C, et al. Gastrointestinal manifestations in myotonic muscular dystrophy. World J Gastroenterol 2006; 12:1821.
  114. Tieleman AA, van Vliet J, Jansen JB, et al. Gastrointestinal involvement is frequent in Myotonic Dystrophy type 2. Neuromuscul Disord 2008; 18:646.
  115. Tieleman AA, Knuijt S, van Vliet J, et al. Dysphagia is present but mild in myotonic dystrophy type 2. Neuromuscul Disord 2009; 19:196.
  116. D'Angelo MG, Bresolin N. Cognitive impairment in neuromuscular disorders. Muscle Nerve 2006; 34:16.
  117. Meola G, Sansone V, Perani D, et al. Reduced cerebral blood flow and impaired visual-spatial function in proximal myotonic myopathy. Neurology 1999; 53:1042.
  118. Meola G, Sansone V, Perani D, et al. Executive dysfunction and avoidant personality trait in myotonic dystrophy type 1 (DM-1) and in proximal myotonic myopathy (PROMM/DM-2). Neuromuscul Disord 2003; 13:813.
  119. Gaul C, Schmidt T, Windisch G, et al. Subtle cognitive dysfunction in adult onset myotonic dystrophy type 1 (DM1) and type 2 (DM2). Neurology 2006; 67:350.
  120. Sansone V, Gandossini S, Cotelli M, et al. Cognitive impairment in adult myotonic dystrophies: a longitudinal study. Neurol Sci 2007; 28:9.
  121. Heatwole CR, Miller J, Martens B, Moxley RT 3rd. Laboratory abnormalities in ambulatory patients with myotonic dystrophy type 1. Arch Neurol 2006; 63:1149.
  122. Achiron A, Barak Y, Magal N, et al. Abnormal liver test results in myotonic dystrophy. J Clin Gastroenterol 1998; 26:292.
  123. Panayiotopoulos CP, Scarpalezos S. Dystrophia myotonica. Peripheral nerve involvement and pathogenetic implications. J Neurol Sci 1976; 27:1.
  124. Logullo F, Censori B, Danni M, et al. Peripheral neuropathy in myotonic dystrophy: electrophysiological and clinical features. Electromyogr Clin Neurophysiol 1992; 32:515.
  125. Olson ND, Jou MF, Quast JE, Nuttall FQ. Peripheral neuropathy in myotonic dystrophy. Relation to glucose intolerance. Arch Neurol 1978; 35:741.
  126. Gadalla SM, Lund M, Pfeiffer RM, et al. Cancer risk among patients with myotonic muscular dystrophy. JAMA 2011; 306:2480.
  127. Mueller CM, Hilbert JE, Martens W, et al. Hypothesis: neoplasms in myotonic dystrophy. Cancer Causes Control 2009; 20:2009.
  128. Meola G, Sansone V. Cerebral involvement in myotonic dystrophies. Muscle Nerve 2007; 36:294.
  129. Minnerop M, Luders E, Specht K, et al. Grey and white matter loss along cerebral midline structures in myotonic dystrophy type 2. J Neurol 2008; 255:1904.
  130. Lieberman AP, Fischbeck KH. Triplet repeat expansion in neuromuscular disease. Muscle Nerve 2000; 23:843.
  131. Rudnik-Schöneborn S, Zerres K. Outcome in pregnancies complicated by myotonic dystrophy: a study of 31 patients and review of the literature. Eur J Obstet Gynecol Reprod Biol 2004; 114:44.
  132. Rudnik-Schöneborn S, Schneider-Gold C, Raabe U, et al. Outcome and effect of pregnancy in myotonic dystrophy type 2. Neurology 2006; 66:579.
  133. Merlini L, Sabatelli P, Columbaro M, et al. Hyper-CK-emia as the sole manifestation of myotonic dystrophy type 2. Muscle Nerve 2005; 31:764.
  134. Logigian EL, Ciafaloni E, Quinn LC, et al. Severity, type, and distribution of myotonic discharges are different in type 1 and type 2 myotonic dystrophy. Muscle Nerve 2007; 35:479.
  135. Young NP, Daube JR, Sorenson EJ, Milone M. Absent, unrecognized, and minimal myotonic discharges in myotonic dystrophy type 2. Muscle Nerve 2010; 41:758.
  136. Miller TM. Differential diagnosis of myotonic disorders. Muscle Nerve 2008; 37:293.