Molecular studies on ancient M. tuberculosis and M. leprae: methods of pathogen and host DNA analysis.

Humans have evolved alongside infectious diseases for millennia. Despite the efforts to reduce their incidence, infectious diseases still pose a tremendous threat to the world population. Fast development of molecular techniques and increasing risk of new epidemics have resulted in several studies that look to the past in order to investigate the origin and evolution of infectious diseases. Tuberculosis and leprosy have become frequent targets of such studies, owing to the persistence of their molecular biomarkers in ancient material and the characteristic skeletal lesions each disease may cause. This review examines the molecular methods used to screen for the presence of M. tuberculosis and M. leprae ancient DNA (aDNA) and their differentiation in ancient human remains. Examples of recent studies, mainly from Europe, that employ the newest techniques of molecular analysis are also described. Moreover, we present a specific approach based on assessing the likely immunological profile of historic populations, in order to further elucidate the influence of M. tuberculosis and M. leprae on historical human populations.

Mitochondrial DNA genetic diversity and LCT-13910 and deltaF508 CFTR alleles typing in the medieval sample from Poland.

We attempted to confirm the resemblance of a local medieval population and to reconstruct their contribution to the formation of the modern Polish population at the DNA level. The HVR I mtDNA sequence and two nuclear alleles, LCT-13910C/T SNP and deltaF508 CFTR, were chosen as markers since the distribution of selected nuclear alleles varies among ethnic groups. A total of 47 specimens were selected from a medieval cemetery in Cedynia (located in the western Polish lowland). Regarding the HVR I profile, the analyzed population differed from the present-day population (P = 0.045, F(st) = 0.0103), in contrast to lactase persistence (LP) based on the LCT-13910T allele, thus indicating the lack of notable frequency changes of this allele during the last millennium (P = 0.141). The sequence of the HVR I mtDNA fragment allowed to identify six major haplogroups including H, U5, T, K, and HV0 within the medieval population of Cedynia which are common in today's central Europe. An analysis of haplogroup frequency and its comparison with modern European populations shows that the studied medieval population is more closely related to Finno-Ugric populations than to the present Polish population. Identification of less common haplogroups, i.e., Z and U2, both atypical of the modern Polish population and of Asian origin, provides evidence for some kind of connections between the studied and foreign populations. Furthermore, a comparison of the available aDNA sequences from medieval Europe suggests that populations differed from one another and a number of data from other locations are required to find out more about the features of the medieval gene pool profile.

Changes in frequency of IDDM-associated HLA DQB, CTLA4 and INS alleles.

The incidence of type 1 diabetes is increasing worldwide. In Poland, the number of cases tripled during the last two decades. The aim of this study was to test the hypothesis that the increase may be at least partly explained by a shift in predisposing alleles' frequencies - resulting from treating the otherwise lethal disease, generally better health care as well as selective pressure imposed by pathogens affecting humankind throughout history. The source of DNA was skeletal remains of 232 individuals excavated in four burial sites, dating back to 11th-14th centuries. With all necessary precautions required in ancient DNA analysis, frequencies of HLA DQB(57), CTLA4+49A/G and INS -23A/T alleles were assessed and compared with available data, characterising contemporary Polish population. Frequency of HLA DQB(57-Asp) protective allele is much higher in present-day population of Poland (50.6%) than in the group of 155 medieval specimens successfully typed for this polymorphism (28.4%, P < 0.001). Out of 86 medieval individuals typed for CTLA4+49A/G, 29.1% were homozygous for the predisposing G allele, which is significantly more than contemporarily - 7.6% (P < 0.001). No statistically significant difference was found in alleles and genotypes frequencies of INS-23A/T polymorphic site. Contrary to the initial assumptions, genetic predisposition towards type 1 diabetes, conferred by HLA DQB(57), CTLA4+49A/G and INS -23A/T alleles is much lower contemporarily than it was approximately 700 years before present. This suggests involvement of other than genetic factors in the fast growing incidence of the disease.

Sex diagnosis of subadult specimens from Medieval Polish archaeological sites: metric analysis of deciduous dentition.

The subject of this work is the characterisation of the metric features of deciduous dentition in a Medieval population of central Poland with the use of the jackknife technique leave one out (LOO)-supporting multivariate methods, which are important for deriving discrimination equations that would result in sex determination of children's skeletal remains. The sex of the individuals was assessed through analysis of sex-specific DNA sequences (AMELY/AMELX, SRY and alpha satellite sequences). Discriminant analysis concerned only teeth of those individuals whose sex was confirmed by the primary structure of three DNA sequences. The deciduous tooth diameters of males were found to be significantly larger than those of females in four respects: MD diameter of the maxillary second molar, MD and BL diameters of the mandibular first molar and BL diameter of the mandibular second molar. A two-group discriminant analysis considered all those measurements as independent variables. A multiple regression procedure produced a linear equation predicting the sex of children's skeletons with a significant probability amounting to approximately 78%. The accuracy of the sex assessment of an individual, using dental measurements, was established at 69% in deciduous male and 88% in deciduous female teeth.

Extremely high frequency of autoimmune-predisposing alleles in medieval specimens.

The precise etiology and reasons for the increase in incidence of autoimmune disorders still remain unclear, and although both genetic and environmental factors have been proven to shape individual predisposition, it is not known which of the factors, if not both, is responsible for the boom observed during the last decades. In order to establish whether a higher frequency of autoimmune-predisposing alleles may explain this increase we took advantage of ancient DNA methodology to establish the genetic predisposition, conferred by cytotoxic T lymphocyte associated antigen-4 (CTLA4) +49A/G and human leukocyte antigens (HLA) DQB1(57), in population inhabiting Poland in the Middle Ages. After successful typing of 42 individuals from a 12th approximately 14th's century archeological burial site, we found that frequencies of the predisposing alleles in the medieval population were higher than they are at present, suggesting thus that the recently observed incidence increase results most probably from factors of other than genetic nature.

Do determinants of platelet function co-segregate with genetic markers of type 1 diabetes mellitus?

This study examined the significance of selected parameters of primary haemostasis to discriminate between relatives of children with insulin-dependent diabetes mellitus (IDDM). Platelet function, including markers of spontaneous and agonist-induced platelet activation (CD62), platelet consumption (microparticles) and clumping (aggregates), as well as selected parameters of the fibrinolytic system (t-PA and PAI-1), were studied in IDDM children ( n = 45), their parents ( n = 65), siblings ( n = 17) and unrelated healthy controls ( n = 51). The fraction of activated platelets circulating in whole blood amounted to 4.3 +/- 2.1% in IDDM children, and significantly exceeded the level found in parents (1.3 +/- 0.7%, P < 0.002), siblings (1.2 +/- 1.0%, P < 0.002), and controls (1.2 +/- 0.6%, P < 0.002). Furthermore, an enhanced formation of platelet microparticles was observed in the IDDM group, both in resting platelets and also when platelets were stimulated with thrombin. Significantly decreased total PAI-1 occurred in IDDM children ( P < 0.02 versus parents); also slightly lowered active PAI-1 and t-PA antigen were noticed in IDDM subjects compared to other groups, however, the differences were not statistically significant. To assess dissimilarities between the groups of subjects we applied the forward stepwise model of discriminant function analysis, which included platelet flow cytometry parameters. The best separation and the highest discrepancy (expressed as the so called squared Mahalanobis distances, d ) was M revealed between controls and IDDM patients ( P < < 0.0001) and between controls and parents ( P < < 0.0001). The values of d found between IDDM children and their siblings (P < 0.001), as well as parents ( P < 0.01), were M of much lower significance. The finding that the control group, representing unrelated subjects, remains particularly well separated from the other groups, more or less clustered together, implies the possible involvement of genetic factor(s) which might potentially affect platelet activation and reactivity. In addition, the distinguished distribution of HLA DQAI(52) and HLA DQBI(57) genotypes in the groups further validates the suspicion that the altered platelet function and response in diabetes might be associated with some independent genetic factor(s), and is not likely to result from HLA DQAI(52) and HLA DQBI(57) impact.

Purification of low molecular weight metal-binding proteins by preparative polyacrylamide gel electrophoresis: properties of electrophoretically purified rat liver (Cd, Zn) - metallothioneins.

A method is proposed for purification of metallothionein by preparative polyacrylamide gel electrophoresis. The method enables purification of 100-700 mg of a preparation containing (Cd, Zn) - metallothionein yielding preparations of considerably higher purity as compared with those obtained by ion-exchange chromatography.