In addition, patients with any of the clinical forms of MMD, but especially males, are reported to have reduced fertility ( Harper, 1989). The wide range of the qualitative and quantitative variations of the clinical findings of MMD patients depends on the extent of gene mutation in the different patients (grades I, II, III, IV). Respectively these may include hypotonia of striated and smooth muscle and cardiac muscle conduction defects, ophthalmological pathologies such as cataracts and mental retardation due to endocrine deficiencies. The mutated gene expresses an abnormal muscle membrane protein kinase and consequently MMD patients present symptoms and signs of muscular, central nervous system and endocrine disorders.
The mutation that causes myotonic dystrophy is the expansion of the CGT triplets at the 3′ end of the gene, that, in turn, is located on chromosome 19 (19q12) ( Buxton et al., 1992 Harley et al., 1992). Myotonic muscular dystrophy (MMD) is defined as a hereditary, autosomal dominant disease characterized by the development of structural and functional abnormalities of the muscle membrane protein myotoninkinase involved in protein phosphorylation ( Roses and Apple, 1973, 1974). Acrosome reaction, dystrophy, d-mannose, spermatozoa Introduction