Estonian Population Research Articles

Konstantin Pätsi „Maa-küsimus“ ja selle ajalooline kontekst [Abstract: Konstantin Päts’s “The land question” and its historical context

At the beginning of the 20th century, most rural land in the provinces of Estland and Livland belonged to the Baltic German landlords. Although a growing number of peasant farms had emerged, most of the peasantry remained landless. Therefore, the problem of land ownership or the land question was particularly important for the Estonian population. The Russian Revolution of 1905 had a far-reaching impact on the development of Estonian political thought. Following the October Manifesto, the first Estonian political parties were founded. As the First State Duma convened in St. Petersburg at the end of April 1906, it was expected that the land question would be resolved. In May of 1906, the Russian Constitutional Democratic Party (Kadets) drafted a land reform bill proclaiming a partial expropriation of private land and the formation of a state land reserve. In the subsequent months, the draft bill launched a public debate in local Estonian and Baltic German newspapers. At the heart of the dispute lay the question of how to redistribute the expropriated land. The liberal newspaper Postimees called for the sale of the expropriated land as small farms. More radical newspapers Vaatleja, Sõnumed, Koit and Virulane supported the perpetual lease of expropriated land. The Baltic German newspapers used legal as well as economic arguments against the radical land reform bill. In fact, the Baltic Germans found the bill to be an unfeasible utopia that could devastate Russian agriculture. The aim of this article is to examine Konstantin Päts’s “The land question” (1907) in the context of the aforementioned debate and to throw light on the origins of Päts’s political ideas. “The land question” is the most comprehensive text written by Päts from that period. In “The land question”, Päts outlines his land reform programme, which favours the partial expropriation of private land, the formation of a provincial land reserve and the redistribution of expropriated land to landless peasants under the perpetual lease system. Päts points out that long-term leasehold has several advantages compared to small farm ownership and concludes that lease in perpetuity is especially beneficial for less-wealthy farmers. Päts contests the claim that private land ownership is the prerequisite for agricultural development. At the same time, Päts clearly discerns himself from socialists and argues that the expropriation of land for public purposes is not unknown to liberal ideology. Päts’s land reform proposal differs from the Kadets’ land reform bill in that it requests a larger land norm and demands local autonomy in all decisions regarding the provincial land reserve. Hereby Päts insists on unifying Estland and northern Livland into one national autonomous province. At the beginning of “The land question”, Päts gives an overview of agrarian reform in New Zealand. For Päts, New Zealand’s agrarian policy is an excellent model for the Baltic provinces. In New Zealand, the government had bought land from large landowners. As a result, small farmers had an opportunity to acquire land on perpetual lease. When justifying his land reform proposal, Päts repeatedly quotes the works of Adolf Damaschke, the leader of the Union of German Land Reformers. Indeed, Damaschke’s standpoint concerning the common ownership of land had significantly influenced the political views of Päts. More broadly, Päts’s belief in the social nature of land property reflects the impact of contemporary land reform movements at that time initiated by the American social thinker Henry George. KEYWORDS: Konstantin Päts, land reform proposals, perpetual lease, Russian Revolution of 1905, Baltic provinces, Estonian political thought.

Highly variable clonal diversity and spatial structure in populations of sickle medic

Abstract Clonal diversity and spatial structure in six remnant Estonian populations of sickle medic Medicago sativa ssp. falcata growing in different habitat conditions were estimated at three different spatial scales, in 1 m 2 and 4 m 2 small-scale plots and in 30–60 m long linear transects, using four polymorphic isozyme markers. Sampling all ramets in fourteen 1 m 2 quadrates yielded 419 ramets which displayed 113 multilocus genotypes (MLGs), whereas 311 ramets from 4 m 2 plots exhibited 144 genets and 262 ramets in six transects revealed 223 genets. All MLGs except two were distinct, indicating extremely high genotypic diversity and strong differentiation among populations. Highly variable small-scale spatial structure with adjacent ramets of identical MLGs and different sizes was detected in quadrates up to monoclonality of some plots. Differences in local disturbances and land-use history of populations were found to be associated with their variable genotypic structure and diversity. Sexual reproduction was locally suppressed in abandoned grassland at places with a dense cover of competing grasses and thick litter layer, however, still occurring in suitable or disturbed places. Strong competition at sites densely covered with adult plants has led to the local elimination of small clones and preferential spread of survived clones. High clonal richness observed in long transects with up to 100% consisting of unique MLGs suggests ability of sickle medic for repeated sexual reproduction in established populations. Local disturbances are supposed to provide suitable microsites for seedling recruitment, evidenced by the presence of unique and small MLGs of recent origin.

Taste sensitivity to PTC and colour blindness in Estonians

The article discusses the genetic characterisation of Estonians on the basis of the traits of PTC and colour blindness in Estonian population samples from various parts of Estonia. The taste sensitivity to PTC was studied in 2559 Estonian schoolchildren from 24 localities and of colour blindness in 4300 males from 33 localities. Results: The frequency of nontasters was 25.4% on average; t gene frequency (50.4% for Estonians) varied between 36% and 65%. PTC nontasters frequency is higher on West-Estonian islands and in Western Estonia compared to other parts of Estonia. The frequency of colour blindness cb gene (5.3% for Estonians) is higher in North, North-East and East Estonia (6–8%); its mean frequency on the rest of the territory is lower. The genetic diversity in various traits seem to be a trace of the historical development of the Estonian nation.

Stroke Awareness in Two Estonian Cities: Better Knowledge in Subjects with Advanced Age and Higher Education

Objectives: This study was undertaken to assess stroke awareness of the Estonian population. Methods: Investigators were asked to fill in an original, closed-ended multiple-choice questionnaire about the definition, risk factors, symptoms and behavior at the onset of stroke by randomly selected subjects in public places of the two biggest cities in Estonia (Tallinn and Tartu). Results: The study included 355 persons. Most of the respondents knew that stroke is an acute disease and that one should call the ambulance at the onset of a stroke. Speech disorder and paresis were the best known symptoms, while hypertension was the best known risk factor. There were no differences between the sexes, but advanced age and higher level of education were related to higher awareness. Conclusions: The overall knowledge was better compared to many other studies. Future awareness campaigns should be addressed to younger subjects with lower education.

Survivin promoter polymorphisms and autoantibodies in endometriosis

Expression of survivin, an inhibitor of apoptosis, is increased in endometriotic lesions and probably favors the survival of endometrial fragments in the peritoneal cavity. The aim of this study was to evaluate associations between survivin promoter polymorphisms and the risk of endometriosis, as well as to compare the immunoreactivity to survivin in sera of patients with and without endometriosis. We studied 149 women with endometriosis, 196 fertile women from the general population (control group A) and 47 women who had undergone diagnostic laparoscopy and had no evidence of endometriosis (control group B). There were no significant differences in the genotypic distribution of the survivin gene promoter region −241C/T, −235G/A and −31G/C single nucleotide polymorphisms (SNP) between endometriosis patients and the two control groups. In addition, also median anti-survivin autoantibody levels were similar among patients and controls (group B). However, anti-survivin antibody concentrations seemed to be influenced by cigarette smoking, being significantly lower in sera of actively smoking women compared to non-smokers (median OD: 0.019 vs. 0.155, respectively, P<0.001), and by the −235G/A SNP, as A allele carriers were significantly more frequent among women with a high antibody level (OD≥2.0) compared to those with lower concentrations (OD<2.0) (23.1% vs. 4.1%, respectively, P=0.008). Based on these results, we conclude that survivin promoter polymorphisms are not associated with susceptibility to endometriosis in the Estonian population, and though the expression of survivin is increased in endometriotic lesions, autoimmune reactivity against it is similar in women with and without the disease.

Bucking the Trend in Wolf-Dog Hybridization: First Evidence from Europe of Hybridization between Female Dogs and Male Wolves

Studies on hybridization have proved critical for understanding key evolutionary processes such as speciation and adaptation. However, from the perspective of conservation, hybridization poses a concern, as it can threaten the integrity and fitness of many wild species, including canids. As a result of habitat fragmentation and extensive hunting pressure, gray wolf (Canis lupus) populations have declined dramatically in Europe and elsewhere during recent centuries. Small and fragmented populations have persisted, but often only in the presence of large numbers of dogs, which increase the potential for hybridization and introgression to deleteriously affect wolf populations. Here, we demonstrate hybridization between wolf and dog populations in Estonia and Latvia, and the role of both genders in the hybridization process, using combined analysis of maternal, paternal and biparental genetic markers. Eight animals exhibiting unusual external characteristics for wolves - six from Estonia and two from Latvia - proved to be wolf-dog hybrids. However, one of the hybridization events was extraordinary. Previous field observations and genetic studies have indicated that mating between wolves and dogs is sexually asymmetrical, occurring predominantly between female wolves and male dogs. While this was also the case among the Estonian hybrids, our data revealed the existence of dog mitochondrial genomes in the Latvian hybrids and, together with Y chromosome and autosomal microsatellite data, thus provided the first evidence from Europe of mating between male wolves and female dogs. We discuss patterns of sexual asymmetry in wolf-dog hybridization.

Changes in high-risk sexual behaviour among Estonian adults between 1996 and 2006

ObjectiveTo describe and compare sexual behaviour patterns in 1996 (before the explosion of the HIV epidemic in 2000) and 2006, and the correlates of high-risk sexual behaviour in Estonia.MethodsData on...

Host plant relationships of an endangered butterfly, Lopinga achine (Lepidoptera: Nymphalidae) in northern Europe

The aim of the present study was to evaluate—in a geographic perspective—the role of host plant as a determinant of habitat quality for Lopinga achine, a satyrine butterfly endangered over much of its European range. Laboratory trials were performed to record host choices made by the ovipositing females as well as by neonate larvae. In rearing experiments, growth performance and mortality on different host plants was determined. Oviposition was found to be indiscriminate but larvae were shown to be able to choose between host plants, with the choices made broadly consistent with growth performance of the larvae on particular hosts. Nevertheless, most grasses and sedges offered were found to support larval development reasonably well. No clear superiority of the previously suggested primary host plant Carex montana could be shown. Importantly, no differences in host plant relationships were found between the populations of Sweden, western Estonia and eastern Estonia. In particular, the larvae originating from eastern Estonian populations developed on C. montana equally well even if the plant is absent from their native habitat. In the context of species conservation, one should conclude that L. achine is polyphagous enough on various grasses and sedges so that the presence of any particular host species cannot be a critical component of habitat quality. Nevertheless, some preference to broad- and soft-leaved hosts, as well as sensitivity to host wilting, may partly explain the butterfly’s preference to moist forest habitats, further emphasizing the central role of habitat management in the conservation practice of this species. In turn, the absence of ecological differences between geographic populations should enable conservationists to successful transfer their experience across national boundaries.

Analysis of genetic variants of class II cytokine and their receptor genes in psoriasis patients of two ethnic groups from the Volga-Ural region of Russia

The molecular basis of pathogenesis of psoriasis remains unclear, but one unifying hypothesis of disease aetiology is the cytokine network model. The class II cytokines (CF2) and their receptors (CRF2) are all involved in the inflammatory processes and single nucleotide polymorphisms (SNPs) in respective genes have been associated with psoriasis in a previous study of the Estonian population. We performed a replication study of 47 SNPs in CF2 and CRF2 genes in independent cohorts of psoriasis patients of two ethnic groups (Russians and Bashkirs) from the Volga-Ural region of Russia. DNA was obtained from 395 psoriasis patients of two ethnic groups from the Volga-Ural region of Russia and 476 ethnically matched controls. 47 SNPs in the loci of the genes encoding Class II cytokines and their receptors were selected by SNPbrowser version 3.5. Genotyping was performed using the SNPlex™ (Applied Biosystems) platform. The genetic variant rs30461 previously associated in original case-control study in Estonians, was also associated in Russians (corrected P-value (Pc=0.008, OR=0.44), but did not reach statistical significance in the Bashkir population. Additionally, the haplotype analysis provided that CC haplotype formed by the SNPs rs30461 and rs955155 had a protective effect in Russians (Pc=0.0024, OR=0.44), supporting the involvement of this locus in the protection against psoriasis. Combined meta-analysis of three populations, including 943 psoriasis patients and 812 healthy controls, showed that the IL29 rs30461 C-allele was not associated with decreased risk of psoriasis (P=0.165, OR=0.68). Moreover, stratification of studies by ethnicity revealed a significant association in the European cohort (P=9.506E-006, OR=0.53). Therefore, there is no overall evidence of association between psoriasis and SNP rs30461 of the IL29 gene, but there is some evidence to suggest that an association exists in Europeans. However, this current concept should be considered as preliminary and the results need to be confirmed in future independent studies.

High incidence of traumatic spinal cord injury in Estonia

Retrospective population-based cohort study. To provide national data on epidemiology of traumatic spinal cord injury (TSCI) among the population of Estonia from 1997 to 2007. All Estonian hospitals. Medical records of patients with TSCI from all regional, central, general and rehabilitation hospitals in Estonia were retrospectively reviewed. Epidemiological characteristics, etiology, neurological level and severity of injury, concomitant injuries were analyzed. A total of 595 patients with TSCI from 1 January 1997 to 31 December 2007 were identified. The male to female ratio was 5.5:1. The mean age at injury was 39.0 years. The crude incidence rate was 39.7 (95% confidence interval: 36.6-43.0) per million population. The most frequent cause of TSCI was falls (41%), followed by traffic accidents (29%). Alcohol consumption preceded 43% of injuries. The lesion level was cervical in 59.4%, thoracic in 18.3% and lumbar/sacral in 22.3%. Compared to recent studies from Europe, where the incidence of TSCI is between 15 and 30 per million population, the incidence of TSCI in Estonia is among the highest. The rates are significantly higher in men compared with women and especially among the youngest men. The leading cause of TSCI is falls. A significant proportion of injuries are related to alcohol consumption before trauma in Estonia.

Probing the perceptual and cognitive underpinnings of braille reading. An Estonian population study

Similar to many sighted children who struggle with learning to read, a proportion of blind children have specific difficulties related to reading braille which cannot be easily explained. A lot of research has been conducted to investigate the perceptual and cognitive processes behind (impairments in) print reading. Very few studies, however, have aimed for a deeper insight into the relevant perceptual and cognitive processes involved in braille reading. In the present study we investigate the relations between reading achievement and auditory, speech, phonological and tactile processing in a population of Estonian braille reading children and youngsters and matched sighted print readers. Findings revealed that the sequential nature of braille imposes constant decoding and effective recruitment of phonological skills throughout the reading process. Sighted print readers, on the other hand, seem to switch between the use of phonological and lexical processing modes depending on the familiarity, length and structure of the word.

No evidence of somatic DNA copy number alterations in eutopic and ectopic endometrial tissue in endometriosis

De novo somatic copy number aberrations (SCNAs) in eutopic and ectopic endometria are thought to be involved in the pathogenesis of endometriosis. In this study we used, for the first time, high-density single nucleotide polymorphism-array technology for accurate detection of SCNAs, inherited DNA copy number variations (CNVs) and copy-neutral loss of heterozygosity (cn-LOH) patterns in patients with endometriosis. The Illumina HumanOmniExpress array was used to detect de novo somatic genomic alterations in eutopic and ectopic endometria from 11 women (eight with Stage I-II endometriosis and three with Stage III-IV endometriosis) by comparatively analysing DNA from peripheral blood, eutopic endometrium and a pure population of endometriotic cells harvested from endometriotic lesions by laser capture microdissection (LCM). The frequency of the CNV in 3p14.1 from blood DNA of 187 endometriosis patients (94 with Stage I-II endometriosis and 93 with Stage III-IV endometriosis) and 171 healthy women from the Estonian general population was evaluated. Analysis of array data showed that LCM DNA can be used successfully for detection of genetic changes as all inherited CNVs were identified in all tissues studied. No unique SCNAs or cases of cn-LOH were found in either eutopic or ectopic endometrium when compared with blood DNA. The frequency of the deletion allele in 3p14.1 did not differ between studied groups. In the present study no endometriosis-specific SCNAs or regions of cn-LOH in eutopic or ectopic endometrium were found. Nevertheless, as we studied only 17 endometriotic tissues derived from 11 patients we cannot entirely exclude the occurrence of rare SCNAs. Based on our results we suggest that molecular mechanisms other than chromosomal rearrangements most likely underlie the onset and progression of endometriosis.

The structure of mating type, virulence, metalaxyl resistance of Phytophthora infestans in a long-term phenotypic study in distinct location in Eastern Estonia

The potato late blight pathogen Phytophthora infestans was collected from a region of Eastern Estonia during a period of seven years (2001–07). In total, 180 isolates were assessed for virulence, 133 for mating type and 171 for metalaxyl resistance. The average frequencies of mating types A1 and A2 were 59% and 38%, respectively. Considerable differences in the proportion of A1 and A2 between years were found. The data indicate that, in the Estonian population of P. infestans, both mating types occurred simultaneously within fields, with the potential for sexual recombination. The relatively rare virulence factors 5 and 9 and the less frequent virulence factors 2, 6, 8 were found in all studied years. Racial diversity, calculated with normalised Shannon diversity index, was high (0.71) but did not show significant differences between different collection years. The data showed that the response of isolates to metalaxyl did not depend on the year of collection. Still, the interaction was considerable between response to metalaxyl and the year, which means that the proportion of sensitive isolates increased and the proportion of intermediate isolates decreased notably compared to other concentration variants. By contrast, metalaxyl resistant isolates remained at a similar level during the seven year period.

Lower limbs functional abilities in middle- aged estonian population with different radiographic grades of knee osteoartrthritis

s / Osteoarthritis and Cartilage 20 (2012) S54–S296 S165 However, diabetes/hyperglycemia and/or dyslipemia artes were not different between groups. Metabolic syndromewas also significantly more prevalent among patients with KOA (Table). When analyzing the history of complications of cardiovascular disease such as ischemic heart disease or cerebrovascular complications, patients with KOA also showed a significantly higher rate as compared with the control group (16/184 (61.5%) vs. 9/254 (3.5%), p <0.05). [Table] KOA (n1⁄4 184) Control (n1⁄4 254) p % female 79.3% 66.9% age (years) 67.9 9.3 63.2 8.4

Phylogeography of the threatened butterfly, the woodland brown Lopinga achine (Nymphalidae: Satyrinae): implications for conservation

We have studied the phylogeography of the red-listed Palearctic butterfly Lopinga achine (Nymphalidae: Satyrinae) based on 1,450 base pairs of mitochondrial DNA sequences from 86 individuals representing 12 populations. Our results indicate a strong structuring of genetic variation, with among-population differences accounting for ca. 67% of the variation and almost all populations being significantly differentiated from each other. We surmise that the insular nature of populations as well as the low dispersal ability of the species has given rise to such a pattern. The genetic diversity within populations is low compared to that in other butterflies. Our results point to a scenario where the species originated in the Eastern Palearctic and expanded into Europe. Based on the analyses, we suggest that the Czech population merits the highest conservation priority. The two Swedish populations represent a distinct evolutionary lineage, and hence merit high conservation attention. The Estonian and Asian populations had the highest genetic diversity, and although we do not consider them to be under immediate threat, their genetic diversity should be conserved in the long term.

LADA and T1D in Estonian population — Two different genetic risk profiles

Aims/hypothesisThe aim of our study was to analyze combined impact of 17 polymorphisms at 8 gene regions previously shown to be associated with autoimmunity in diabetes. We hypothesized that the genetic predisposition is multiplicative and joint risk of different diabetic phenotypes forms by distinct combination of susceptibility loci. MethodsAn ethnically homogenous population of Estonian origin, including 65 LADA patients, 154 patients with T1D, 260 patients with T2D and 229 non-diabetic controls, was genotyped for polymorphisms/haplotypes in HLA-DQB1, insulin gene (rs689, rs3842729), PHTF1–PTPN22 region (rs2476601, rs6679677), CTLA4 region (rs231806, rs16840252, rs5742909, rs231775, rs3087243, rs2033171), ICOS region (rs10932037, rs4675379), CD25 (rs706778), CD226(rs763361), NAA25 (rs17696736). ResultsAs expected, the risk of T1D was consistently attributed by HLA-DQB1 haplotypes, but also by haplotypes of INS and PHTF1–PTPN22 region, and rs17696736 in NAA25. By contrast, LADA was associated only with T1D-protective HLA haplotypes and with two more frequent haplotypes of the CTLA4. It is of interest, that seldom CT haplotype of PHTF1–PTPN22 region carried the risk for autoantibody-negative T2D. The final best-fitted model for T1D genetic risk contained six gene regions (HLA-DQB1, INS, PHTF1, CTLA4 +49, CD226 and NAA25) and for LADA only two (HLA-DQB1 and CTLA4 +49). The AUCs of these models are 0.869 and 0.693, respectively. ConclusionsClassical T1D-risk haplotypes of HLA and some non-HLA loci describe quite well the genetic risk for T1D but not for LADA. The need of further studies should be stressed to discover the real risk factors for slower forms of autoimmune diabetes in adults.

A 10-year serological follow-up of celiac disease in an Estonian population

Celiac disease (CD) is induced by wheat gluten and related prolamines. Its prevalence may be underestimated in many geographic regions and populations, and has recently increased in several countries. In 1998 and 1999, a random sample of Estonian schoolchildren was screened with IgA-type tissue transglutaminase antibodies (IgA-tTG) for CD. The results revealed a CD prevalence of 0.34%, which is lower compared with many other European countries. We rescreened the same population for CD using IgA-tTG after a 10-year interval. A total of 891 patients from the initial sample were rescreened using the IgA-tTG assay for a participation rate of 76.8% (median age, 24.3 years). As in the initial study, the IgA-tTG results were evaluated by ImmunoCAP EliA Celikey using an IgG-tTG and deamidated gliadin antibody assay for IgA-deficient cases. No new cases of CD were found in this follow-up study. Of note, 75% of patients with initial IgA-tTG-positive results and biopsy-proven CD remained seropositive. One patient with a negative seroconversion at the time of rescreening followed a strict gluten-free diet during the follow-up years. In a 10-year follow-up period, no new cases of CD were found in this Estonian population of school-children and young adults. Therefore, we presume no increase in CD during the last decade among this age group in Estonia. Additional studies are needed to determine whether similar results would be obtained in other age groups, because of differences in the CD prevalence between Estonian and other European populations.

Identification of Anaplasma phagocytophilum in tick populations in Estonia, the European part of Russia and Belarus

Anaplasma phagocytophilum is associated with diseases of goats, sheep, cattle, dogs and horses. In the beginning of the 1990s it was identified as a human pathogen, causing human granulocytic anaplasmosis (HGA) in the USA, Europe and the far east of Russia. A. phagocytophilum is maintained in nature in an enzootic cycle including ticks as the main vector and a wide range of mammalian species as reservoirs. Ixodes ricinus and I. persulcatus ticks were collected in Estonia, Belarus and the European part of Russia and screened for the presence of A. phagocytophilum by real-time PCR. Positive samples were found only among I. ricinus, in 13.4% in the European part of Russia, 4.2% in Belarus, 1.7% in mainland Estonia and 2.6% on Saaremaa Island. Positive samples were sequenced for partial 16S rRNA, groESL and ankA genes and phylogenetic analyses were performed. The results showed that A. phagocytophilum circulating in Eastern Europe belongs to different groESL lineages and 16S rRNA gene variants and also consists of variable numbers of repetitive elements within the ankA gene.

Assessment of natural radiation exposure from building materials in Estonia

Radionuclides naturally occurring in building materials may significantly contribute to the annual doses of the public. As information on the radioactivity of such materials is lacking, the study of building materials used in Estonia was carried out in order to estimate the annual dose to the Estonian population due to natural radionuclides in building materials. During the study 53 samples of commonly used raw materials and building products were collected and measured. The activity concentrations were determined by gamma ray spectrometry. Their mean values were in the ranges 7–747 Bq kg for K, 4.4–69 Bq kg for Ra, and 0.8–86 Bq kg for Th. The activity index I in the 53 different building materials varied from 0.02 to 0.74 and the radium equivalent, from 6 to 239. The average annual dose for the people, caused by the building materials of dwellings, was assessed for most commonly used materials. It was estimated to be in the range from 0.16 mSv to 0.44 mSv.

The prevalence of cognitive dysfunction in the estonian population of the hereditary spastic paraplegia

The hereditary spastic paraplegias (HSPs) are neu-rodegenerative disorders of the motor system. The information about the prevalence of the cognitive dysfunction in HSP is inconsistent. The aim of the study was to describe the prevalence of cognitive dysfunction and the cognitive profiles of persons with HSP (pwHSP) compared to healthy controls. Subjects. Participating in the cognition study were 48 persons with HSP from the epidemiological study and 48 healthy controls. Of those with HSP, 81% (39/48) had pure and 19% (9/48) had complex forms. Among pwHSP, 20.8% (10/48) had pathogenic and 14.6% (7/48) had non-pathogenic mutations in the SPAST gene. There were no mutations detected in 31 persons with the SPAST gene. Methods. Neuropsychological test battery, MMSE Results. The results of the neuropsychological tests were significantly lower in persons with HSP than in the controls (Bonferroni correction, p < 0.00625). There were statistically significant differences in subtests measuring consistent long term retrieval (p < 0.001), later recall (p = 0.004) in verbal memory and symbol digit modalities (p = 0.0015). Five persons with HSP had an MMSE score of 24 or less. Conclusions. Our results demonstrate that cognitive dysfunction is present in 16.7 to 33.3% of persons with HSP, depending on the criteria applied. There was cognitive dysfunction in 30% of persons with a known pathogenic mutation in the SPAST gene. The most frequently damaged functions in HSP are consistent long term retrieval and later recall in verbal memory and symbol digit modalities tests that discriminate between controls and pwHSP with dysfunction (1.5 SD) in three or more domains. Dementia in HSP is rare.