[Molecular genetic basis of proximal spinal muscular atrophy and experience in its pharmaceutical treatment].

The review considers the original and published data on the molecular genetic basis of proximal spinal muscular atrophy (SMA), the most common monogenic neuromuscular disease. The structures of the SMN1 gene and SMN2 pseudogene, mutations distorting the SMN1 function, the structure and functions of the Smn neurotrophic protein, its role in biogenesis of small nuclear ribonucleoproteins (snRNPs), and the principles and prdblems of molecular diagnosis in SMA are described. Special consideration is given to the current approaches and prospects of gene and cell therapy of SMA, pharmacogenetic methods to correct the SMN2 function, and original results of long-term treatment of SMA patients with valproic acid drugs.

[Clinical polymorphism in respiratory oxalosis]. / Klinicheskii polimorfism pri respiratornom oksaloze.

AIM: Examination of clinical polymorphism of chronic obstructive pulmonary diseases (COPD) in defects of oxalate metabolism to make diagnostic outpatient screening of the preclinical stage. MATERIAL AND METHODS: Diagnostic dysgenetic markers of respiratory oxalosis (RO)--red hair in monthers and 24-h oxaluria--were studied in 28 women and 7 men. 8 women (group 1) had diagnostic association, 7 women (group 2) had no hereditary marker, 13 women (group 3) had no signs of disturbed oxalate metabolism. In addition, families of group 1 patients were examined for preclinical signs of visceral oxalosis in close relatives (kinship degree I). A comparison was made of quantitative enzyme assay of registering 24-h oxaluria (Lartillot M. et Vogel G) and titration by G. A. Sivorinovsky. RESULTS: Group 1 COPD patients with mild disease had rather high 24-h oxaluria. In group 2 and 3 patients oxaluria was significantly lower. Dysgenetic markers--24-h oxaluria with the hereditary criterium--may be used in differential diagnosis of RO with its phenocopy having a more severe course at preclinical stage. Male relatives of kinship degree I had significant differences with group 1 patients in 24-h oxaluria, oxaluria was combined with clinical symptoms of acid, uratic diathesis. CONCLUSION: The enzyme assay of oxalate in 24-h urine in combination with hereditary marker is an adequate screening method for preclinical stage of RO. The presence of various clinical manifestations of visceral oxalosis--RO and acid, uratic diathesis in the family--may indicate clinical polymorphism of mutant gene.

[Contents of alpha-fetoprotein in the blood of pregnant women as a criterion of the presence of congenital heart defects in the fetus]. / Issledovanie soderzhaniia al'fa-fetoproteina v syvorotke krovi beremennykh kak kriteriia nalichiia vrozhdennykh porokov razvitii u ploda.

alpha-Fetoprotein (AFP) was measured in the blood of 16 women pregnant with twins at various terms of gestation and 24 pregnant women whose fetuses were found to have anencephaly, patent spina bifida, gastroschisis, renal polycystosis, or Down's disease. In Down's disease AFP level was 7 ng/ml (0.17 multiple of medians, MoM) at 17 weeks gestation and 6 ng/ml (0.12 MoM) at 19 weeks. In the fetal abnormalities studied AFP level was 372 ng/ml on average (6.8 MoM) at 16 to 18 weeks gestation, this being about 10 times higher than the normal level. AFP level in twin pregnancy at the same period was 2.3 MoM. AFP measurements are important for the prenatal diagnosis of fetal status in order to plan follow-up of pregnancy and labor management.

Molecular forms of ceruloplasmin in hepatolenticular degeneration and their interaction with human erythrocyte ceruloplasmin receptor.

Immunochemical methods were used to show that the sera of homozygous and heterozygous carriers of the Wilsonian gene contain, together with normal ceruloplasmin (CP), a CP-like protein that differs from CP in its enzymatic, immunological, and physicochemical properties. The CP-like protein was isolated from the sera of patients with hepatolenticular degeneration (HLD) by means of affinity chromatography, and monospecific antibodies to this protein were obtained. The presence of an 80 kDa immunoreactive polypeptide specific to the CP-like protein was demonstrated by immunoblotting with antibodies to normal CP and monospecific antibodies to the CP-like protein. Analysis of the ratios of the molecular forms of CP in homozygous and heterozygous carriers of the Wilsonian gene indicated that this ratio reflects the dosage of the mutant gene. The kinetic parameters of the interaction of these proteins with the CP-specific receptor on the erythrocyte membranes from healthy individuals and from patients with Wilson's disease (HLD) were determined. The CP receptor on erythrocyte membranes in HLD patients is not altered and its interaction with normal CP has the same kinetic parameters as the binding of normal CP to the erythrocyte receptors from healthy individuals. The CP-like protein also retains the ability to bind to the CP-specific receptor but the ligand-receptor complex is less stable than in the case of normal CP. The possible mechanism of the molecular heterogeneity of CP in the Wilsonian mutation is discussed.

[Activity of enzymes in amniotic fluid in prenatal diagnosis of cystic fibrosis]. / Issledovanie aktivnosti fermentov amnioticheskoi zhidkosti v prenatal'noi diagnostike mukovistsidoza.

The activity of microvillar enzymes--gamma-glutamyltranspeptidase, aminopeptidase, general and intestinal forms of alkalyne phosphotases was studied in amniotic fluid (AF) of 33 women with 25% risk of cystic fibrosis (CF) (mucoviscidoses) in their progeny. The figures obtained in this group were compared with corresponding values of the same enzymes in 100 AF samples from normal pregnancies (negative control) and with 9 AF samples from women which were known to give birth to the children with CF (positive control). CF has been predicted in 5 cases, pregnancies were artificially terminated in 4 women. Biochemical CF prediction was proved by immunochemical assay of albumin contents in meconium of fetal ileum. One woman from the high risk group refused abortion and gave birth to a CF child. Among 26 cases of low CF prediction, 13 resulted in birth of a child without a sign of CF, one - in a child with clear-cut diagnosis of CF and 12 other pregnancies still proceed. The efficiency of complex biochemical, pathomorphological and molecular approaches for verification of intrauterine CF diagnosis in aborted fetuses as well as for detection of heterozygous carriers of CF gene and prenatal diagnosis of CF is discussed.

[Experience in heterozygote detection in Wilson-Konovalov mutation based on the study of molecular forms of ceruloplasmin]. / Opyt vyiavleniia geterozigot po mutatsii Vil'sona-Konovalova na osnove issledovaniia molekuliarnykh form tseruloplazmina.

A specific novel molecular form of ceruloplasmin (CP) was detected in the sera of Wilson's disease patients and their closest relatives using two-dimensional cross-immunoelectrophoresis. This protein shares some antigenic properties with normal CP but is not completely identical to the latter. Besides, anomalous CP has no oxidase activity of normal CP and differs from it in electrophoretic mobility in agarose and polyacrylamide gels. Anomalous CP was purified to homogeneity and monospecific antibodies to this protein were obtained. The quantitative analysis showed that the ratios of normal CP to anomalous CP in homo- and heterozygous carriers of the "Wilsonian" gene are reproducibly different and can be used as a diagnostic test allowing the differentiation between these groups.

[Molecular defect of ceruloplasmin synthesis and maturation in Wilson-Konovalov disease]. / Molekuliarnyi defekt sinteza i sozrevaniia tseruloplasmina pri bolezni Vil'sona-Konovalova.

The radioimmunochemical study of ceruloplasmin-synthesizing polyribosomes was carried out using bioptic liver specimens obtained from fourteen homozygous patients with hepatolenticular degeneration (Wilson--Konovalov disease) and from eight control patients with various non-hereditary diseases. The measurement of binding of 125I-antibodies to the nascent polysome-bound ceruloplasmin chains demonstrated that in control patients this protein is only synthesized on membrane-bound polysomes, while free polysomes do not contribute to the synthesis of ceruloplasmin. The majority of homozygous carriers of Wilson--Konovalov mutation (eleven of fourteen) are characterized by the involvement of free, rather than membrane-bound polysomes, in the synthesis of ceruloplasmin. This shift of ceruloplasmin synthesis from membrane-bound to free polysomes seems to be accompanied by disturbances in the cotranslational proteolytic maturation of ceruloplasmin from its biosynthetic precursors. As a result of this defect, a putative of ceruloplasmin (preproceruloplasmin) was detected in the content of Golgi complex as well as in the serum of homozygous patients. This precursor of a molecular weight 84,000 was found neither in Golgi complex, nor in the serum of control subjects.

[Clinical polymorphism and ceruloplasmin variants in hepatolenticular degeneration]. / Klinicheskii polimorfizm i varianty tseruloplazmina pri gepatolentikuliarnoi degeneratsii.

The relationship between differences in the clinical polymorphism of hepatolenticular degeneration (Wilson's disease) and characteristics of CP (ceruloplasmin) structural changes were investigated. The comparative study of Wilson's disease patients revealed two forms of clinical development of this disease which differ from each other by the expression of the visceral symptoms preceding the establishment of the typical neurological picture. The peptide map analysis of tryptic hydrolysates of the CP from individual patients has demonstrated the altered peptide patterns in five cases. Clinical and genetic heterogeneity of Wilson's disease is discussed.