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Using multifactorial and monolocus models interrelations of a number of constitutional factors of probands (sex, child convulsive reactions, character abnormalities, age at the time of illness onset) with genetic factors of epilepsy occurrence among relatives (365 families) and populations from 5 regions of the Khabarovsk krai (2.88 patients per 1000 subjects) were studied. The dependence of epilepsy manifestation probability in mutant homo- and heterozygotes on sex, convulsive reactions and age characteristics of the proband body reactivity was shown. The notions of double threshold determination of convulsive readiness (the T1 threshold "cuts" a part of population with non-paroxysmal abnormality of the brain bioelectric activity, while the T2 threshold "cuts" that with convulsive reactions) were substantiated, the presence of this causing epilepsy development in individuals with a mutant allele of the major dominant gene. The hypothesis of the ecogenetic interaction of epilepsy main etiologic factors (major gene, environmental factors and constitutional readiness) has been described.

Genetic-epidemiological analysis of the role of ante-, peri- and postnatal exogenous adversities in the development of epilepsy was performed on the representative sample of 365 families using the multifactor and single locus models. The relationship was established of the genetic factors with ante- and perinatal factors on the one hand, and with postnatal ones on the other. An ecogenetic hypothesis of the epilepsy etiology was put forward.

The article deals with the assessment of the main components and canonic correlations reflecting the relationship between the resources of psychiatric care (a number of beds and psychiatrists providing medical care in hospitals and in other settings) and the rate of identification and incidence of psychoses, schizophrenia, epilepsy, alcoholism, neuroses and oligophrenia in Siberia and Far East over a period of 16 years (from 1965 to 1981 excluding 1978). The first main component covered up to 80.1% of the dispersion range of the identification rate and 94.5% of the incidence rate, the second component covered up to 37.1% and 21% respectively. Canonic correlations proved higher for the incidence rate as against the identification rate. Although there were substantial differences in the studied interrelationship with regard to a number of territories, the main tendency was expressed in a marked linear correlation between a growth in the resources of psychiatric service and the time-course of the rates of the studied pathology.

Based on ITO matrices, a method for parameter estimation of the monolocus diallele model (MDM) of qualitative trait is described, taking account of non-genetic (environmental) factors. The model parameters, probabilities of relatives' affection, constructing the likelihood function and testing hypotheses of the effect of environmental factors on the penetrations of MDM genotypes are outlined. Examples are given, concerning estimation of epilepsy MDM parameters, taking account of two factors-harmfulness of antenatal ontogenesis period and harmfulness which provokes paroxysms.

The initial data for the analysis have resulted in epidemiologic (547 patients) and genetic-epidemiologic (365 patients) study of patients with diagnosis of epilepsy living in five districts of the Khabarovsk Territory. The population frequency of epilepsy was equal to 0.288%. With the use of data on numbers of sick and healthy first-third-degree relatives, and the method of maximum likelihood, the monolocus diallelic model (MDM) parameters of the family and population epilepsy prevalence were estimated. For each of 9 MDM variants two decisions were obtained, depending on the use of population probability of the feature. The analysis of 8 sets of initial data allowed to ascertain the influence of information about the first-third-degree relatives on parameter estimates. The calculation results are presented for one of initial data sets (set A). Three MDM variants were shown to predict the values of the relative affection probability, these being rather close to frequencies observed. The arguments are presented in favour of quasi-dominant variant with following parameters: frequency of mutant allele in a population - 5.28%, homozygote penetrance - 21.5% and that for heterozygote - 2.6%. According to parameter estimates within this model, the probability of offspring disease in the family with the known number of sick and healthy parents was calculated.

The authors have demonstrated the existence of linear correlation between the complex of three factors (the number of beds and psychiatrists in hospitals and outpatient clinics) and incidence rate (over a period of 16 years) of neuroses in 11 administrative areas, epilepsy, in 12 areas, psychoses, in 15, oligophrenia, in 17, alcoholism and schizophrenia in all 18 areas of Siberia and the Far East. Correlations of each of the three factors with the morbidity rate varied within a wide range in relation to both administrative areas and individual diseases. The authors draw attention to the importance of supplementing the growth of resources of psychiatric service with new forms and methods of work.

On the basis of a blanket examination of employees at a large industrial enterprise which revealed 743 patients with neuropsychic diseases, predominantly of a borderline nature, and of 273 mentally normal subjects the authors, using the algorithm of image recognition identified an informative aggregation of factors determining the status of mental health. In the total sample the authors received 85.5% of correct, 13.8% of erroneous, and 0.7% of unrecognized solutions. The authors also discuss signs considered as risk factors and as factors of resistance in relation to the development of neuropsychic abnormalities. The utilization of the results obtained may be promising in conducting the preliminary automatic screening of the population with the purpose of identifying groups at a risk of developing neuropsychic disturbances.

A complex of factors carrying major information on the epileptogenesis was recognized and their interrelation analyzed. Initial sample comprised 14 signs of the patients' constitutional features (532 individuals) and their relatives' mental health (10858 individuals). A model was constructed to represent the interrelation of the signs using an algorithm of logical-+-mathematical image detection realized on an SM-4 computer. Eight signs were entered into a most informative group. The model helped to formulate new theoretical notions of the relationship of constitutional and hereditary factors in epileptogenesis.

The results of the genetic-correlative analysis of schizophrenia (681 families) and epilepsy (365 families) are given. The presence of various liabilities to these diseases, having genetic correlation of 0.16-0.19 between them, is shown. From epidemiologic data, elevated frequency of convulsive manifestations in schizophrenics and schizophrenia-like psychosis in epileptic patients was established. Within the limits of the three-component hypothesis of etiology of these diseases ("major genes", environmental factors and constitutional readiness), the relation detected is explained by interaction between constitutional readiness factors.

The authors compare the factors, parameters and typology of the clinical polymorphism of epilepsy in two groups of patients from an epidemiological sample: 265 patients with a synchronous and 251 patients with an asynchronous circadian pattern of attacks. It has been found that the asynchronous circadian pattern of attacks significantly correlated with a belated psychomotor development, hyperexcitability premorbid characteristics, convulsive manifestations of the disease, marked changes in the personality, the progressive type of the disease course and a number of other unfavourable signs.

With the help of genetic-dispersion analysis the authors studied a series of phenotypes, using both their own familial records (232 families, 5060 relatives of the I-III degree of kinship) as well as those of other researchers (570 families, 18415 relatives of the I-III degree of kinship). The results have shown that the contribution of the genetic and environmental factors to the determination of epilepsy constitutes 5% and 95% in the alternative phenotype model and 65% and 35% in the quasi-continuous phenotype model, respectively. The degree of the genetic factors involvement in the development of phenotypes of "genuine" and "centroencephalic" epilepsy increases irrespective of the phenotype model. The authors also present their outlook on further developments of the genetic dispersion analysis in the research of multifactorial mental diseases.

Estimation of genetic and environmental components of phenotypical dispersion of paroxysmal and nonparoxysmal EEG abnormalities in epilepsy (118 probands and 179 relatives) in two phenotypical model frames has been obtained. The alternative phenotypical model was shown to be more adequate than quasicontinual for EEG abnormalities, and the part of additive genetic component (GA) comprises 15.7% for paroxysmal abnormalities and 49.4% for nonparoxysmal type. In the component type "belonging to one generation" joint influence of genetic and environmental factors on the process of forming EEG abnormalities in ontogeny was observed. The GA value for "epilepsy manifestation" symptom equal to 72.9% in general selection of probands increases to 97.4% in the subgroup of patients with nonparoxysmal abnormalities and 67.4% in the subgroup of patients with paroxysmal EEG abnormalities. It has been suggested that paroxysmal EEG abnormalities reflect their own epileptic process, and as far as nonparoxysmal abnormalities are concerned, they present phenotypical manifestation of the genetic system of predisposition to epilepsy.

Using the algorhythm of a successional statistical Wald procedure, the author elaborated a table for the assessment of the probability of a transition of an exacerbation into remission on the 20th day. The table was tested in the studied group (87 patients) and in control series (94 patients). In a 5% level of permissible error, with the aid of the table a correct prognostical evaluation was attained in 70.5% of the conclusions, incorrect ones in 7.9% and indefinite in 21.0%. Incorrect and indefinite responses prevailed in cases of sclerotomic and radicle lumbo ischalgia. The table is intended for selection of a more severe group, the treatment of which from the beginning of an exacerbation is expedient to conduct in a neurological ward.

The parameters of multifactorial and monolocal models were evaluated according to the incidence indices of the manifested forms of schizophrenia in three population groups of Tomsk regions among the relatives of probands with permanent and attack-like course of the disease. Higher occurrence of mutant homozygotes and increase of the share of these genotypes were detected in permanent course of the manifested schizophrenia. The authors suggest that the differences in genetical parameters of susceptibility to the disease with permanent and attack-like course are caused by influence of constitutional factors on the mutant genes penetrant ability.

The paper contains a comparative analysis of the distribution of the blood groups of the ABO system in 1731 patients with syndromes of spinal osteochondrosis and in 9013 representatives of the population. Besides the frequency indices the authors studied as well the index of a relative morbidity A/O the "racial-biochemical" Hirshfeld index and the relationship of the frequency of group 0 to the sum of frequency in the A, B, AB group. It was demonstrated that there was a significant drop in patients with spinal osteochondrosis of the frequency of the 0 group and an increase of the group A. These deviations demonstrate a correlation with the sex, age by the onset, localization of the process longitudinally to the spine and hereditary loading (cases of repeated cases in the family). The revealed regularities may be considered as evidence of the influence of the genotype on the development of spinal osteochondrosis as well as one of the mechanisms determining the immune response in this disease.

The program of genetic-epidemiological study of schizophrenia in five districts of the Tomsk region is presented. According to standardized methods, 610 diagnosed patients (epidemiological register) were examined, 74.1% of them being at random registered as probands (452 families of the epidemiological sample). 229 probands of non-epidemiological sample were registered in psychiatric hospitals. Schizophrenia occurrence parameters among first-degree relatives of probands of the non-epidemiological sample were regularly overestimated, as compared to the epidemiological sample. The methodical sources of contradictions in clinico-genealogical studies are discussed; the conclusion about representativeness+ of the probands' epidemiological sample is made.