The aim of the study was to evaluate the effects of allelic polymorphism of the FLG and MTHFR genes and their associations in gynecological patients with ichthyosis vulgaris. Gynecological disorders are observed in presence of some forms of ichtyosis. From the prospective of improving nation's healthcare, the greatest attention is drawn to reproductive disorders. Based on this, the research was also tasked with studying of the genetic nature of gynecological diseases, as well as the influence of geographical latitude on the frequencies of mutagenic alleles of the FLG gene and heterogeneous carriers of these mutations. The collection of clinical-gynecological history was carried out by the method of single registration of the proband on the basis of the Regional Clinical Dermatological and Venereological Health Center No. 1 and the Dermatovenerological Health Centers of the Kharkiv Region. The diagnosis and form of dermatosis is established on the basis of the analysis of clinical and gynecological data and the results of laboratory tests in accordance with ICD-10: ichthyosis vulgaris (Q 80.1.0, OMIM 146700). The data on 18 women and 20 men from 3 families, aged 26 to 76 years old, suffering from ichthyosis, were analyzed. As a result of the study, a direct correlation was determined between the latitude and frequencies of mutant alleles of the FLG gene, as well as between the geographical latitude and frequency of heterozygous carriers of these mutations. The frequencies of the T allele and the CT genotype according to polymorphic variant C677T of the MTHFR gene demonstrate feedback with the latitude indicators. The frequency distributions of the 2282del4 allele and the CT genotype, the N/2282del4 and CT genotypes, the 2282del4 and T alleles, the N/2282del4 genotype and the T allele have opposite latitudinal zonation. The established connections made it possible to predict the development of gynecological pathologies in women with ichthyosis vulgaris. The prevalence of endometriosis and endometrial cancer in women with ichthyosis vulgaris in the Kharkiv region was 33.3%, while the average for the female population in the region was 0.29-0.35%. The number of children born to women with ichthyosis vulgaris did not differ from the regional index.