A CASE OF HEREDITARY DISEASE IN ONE FAMILY HAVING SEVERAL CHILDREN WITH DIFFERENT BIOLOGICAL FATHERS

Mucopolysaccharidosis type 1 (МPS 1) is included by the Ministry of Health of the Russian Federation in the list of 700 orphan diseases. The etiopathogenesis of MPS 1 is caused by mutations in the structural gene for the lysosomal enzyme α-L-iduronidase (IDUA), which is the reason for the accumulation of products of incomplete glycosaminoglycan (GAG) disintegration in the cell lysosomes. The mutations are inherited in an autosomal recessive pattern. There are currently more than 100 known mutations in the IDUA gene. Different mutations cause different clinical forms of MPS 1, such as Hurler, Hurler–Sheie, and Sheie syndromes. The polymorphism of clinical manifestations and the low incidence of MPS 1 impede its timely diagnosis and, accordingly, early initiation of therapy. The diagnosis of MPS 1 is based on the identification of the specific phenotype of patients, the determination of the urinary excretion of GAGs and their fractions, tandem mass spectrometry, and DNA diagnosis. Enzyme replacement therapy and bone marrow transplantation improve the follow-up of patients with MPS 1.