Prediction of myotonic dystrophy clinical severity based on the number of intragenic [CTG]n trinucleotide repeats

• Published in: American journal of medical genetics Vol. 65; no. 4; p. 342
• Main Authors: Gennarelli, M, Novelli, G, Andreasi Bassi, F, Martorell, L, Cornet, M, Menegazzo, E, Mostacciuolo, M L, Martinez, J M, Angelini, C, Pizzuti, A, Baiget, M, Dallapiccola, B
• Format: Journal Article
• Language: English
• Published: United States 11.11.1996
• Subjects: Disease Progression; Female; Humans; Male; Myotonic Dystrophy - genetics; Myotonic Dystrophy - physiopathology; Predictive Value of Tests; Trinucleotide Repeats
• ISSN: 0148-7299
• DOI: 10.1002/(SICI)1096-8628(19961111)65:4<342::AID-AJMG18>3.0.CO;2-U

We carried out a genotype-phenotype correlation study, based on clinical findings in 465 patients with myotonic dystrophy (DM), in order to assess [CTG] repeat number as a predictive test of disease severity. Our analysis showed that the DM subtypes defined by strict clinical criteria fall into three different classes with a log-normal distribution. This distribution is useful in predicting the probability of specific DM phenotypes based on triplet [CTG] number. This study demonstrates that measurement of triplet expansions in patients' lymphocyte DNA is highly valuable and accurate for prognostic assessment.