Analysis of HLA-A, C, B, DR and DQ loci in an Italian sample of possible Celtic origin

Trino Vercellese, a village of Piedmont (Italy), was selected with the aim at reconstructing the genetic history of a putative Celtic sample known to be settled in Italy with the name of Rigomagus since pre-roman times. The HLA-A, Cw, B, DR and DQ antigens of 101 unrelated individuals have been typed. The antigens characterizing this sample for their higher frequency are shown to be A3, A11, A32, B35, B39, Bw52, Cw4, DRw11, DRw13, DQw7. Gene frequencies are estimated by maximum likelihood and Hardy-Weinberg equilibrium was tested with no deviant genetic locus. Two-locus haplotype frequencies were also estimated and those with significant associations tabulated. "Extended" haplotypes were reconstructed: the three most frequent haplotypes (covering a total frequency of 11.5%) share the same Cw, B, DR and DQ alleles. Comparisons with other Italian and European samples are indicated to challenge archeological evidence of a pre-roman genetic stratification of the people living in our old Rigomagus.

Effect of aging on left ventricular filling in untreated hypertensive patients

The aim of this study was to evaluate the influence of age and other clinical and echocardiographic parameters on left ventricular filling in a group of 174 untreated patients with mild to moderate hypertension (aged 20-82 years; mean 51.2 years) and in 189 age-matched normotensive subjects. All subjects underwent an echocardiographic study with pulsed Doppler evaluation of left ventricular filling. Left ventricular dimensions and indexes of systolic function were similar and within normal limits in both groups. Left ventricular filling was altered in hypertensive subjects < 65 years with a decrease of peak early velocity (peak E), an increase of peak atrial velocity (peak A) and a reduced E/A ratio. However in subjects > or = 65 years, we did not observe any differences in transmitral flow velocity pattern between hypertensive and normotensive subjects. The stepwise regression analysis showed that age alone explains up to 8% of peak E variance, 14% of peak A and 26% of E/A ratio in hypertensives, while in normotensives it explains up to 18% of peak E variance, 50% of peak A and 61% of E/A ratio. The other variables entered into the regression slightly improved the predictive power. In conclusion, age is the major independent factor affecting left ventricular filling in both groups, even if its predictive power was smaller in the hypertensive group. The similarity of diastolic filling pattern in elderly hypertensive and normotensive subjects suggests that the 'aging factor' plays an important role in influencing left ventricular filling pattern so as to mask the effect of hypertension in the elderly patients.

[Retroperitoneal ganglioneuroma. A case report and review of the literature]

Ganglioneuromas are typically of slow growth and benign evolution and may remain clinically silent for a considerable time if favourably situated. Many large examples are discovered incidentally on X-ray examination, routine abdominal palpation or at necropsy. Ganglioneuromas are often encountered in childhood and are found more frequently in the posterior mediastinum than in any other single situation; other sites are the lumbar and pelvic retroperitoneal tissues, the gastrointestinal tract and the mesentery. Diffuse alimentary tract ganglioneuromatosis has been described as port of the multiple endocrine neoplasia syndrome (MEN) type II-B. Sometimes ganglioneuromas are found in the von Recklinghausen Syndrome. The authors report in this paper a rare case of a retropancreatic ganglioneuromas.

RFLP analysis on a sample from northern Italy

We analysed a sample of 55 unrelated individuals from Trino Vercellese, a village in northern Italy. It represents the only European sample which is unmixed in a comparative study of eight populations from four continents [Bowcock et al 1991a; Lin et al 1994]. RFLP analysis was performed on 32 DNA markers, for a total of 37 independent alleles. Genetic variability between populations was measured by the FST statistics (average FST is 0.138). Average heterozygosity was calculated for each marker and for each population. Genetic distances were evaluated between pairs of populations. Phylogenetic trees were reconstructed and principal component analysis performed.

Demic expansions and human evolution

Geographic expansions are caused by successful innovations, biological or cultural, that favor local growth and movement. They have had a powerful effect in determining the present patterns of human genetic geography. Modern human populations expanded rapidly across the Earth in the last 100,000 years. At the end of the Paleolithic (10,000 years ago) only a few islands and other areas were unoccupied. The number of inhabitants was then about one thousand times smaller than it is now. Population densities were low throughout the Paleolithic, and random genetic drift was therefore especially effective. Major genetic differences between living human groups must have evolved at that time. Population growths that began afterward, especially with the spread of agriculture, progressively reduced the drift in population and the resulting genetic differentiation. Genetic traces of the expansions that these growths determined are still recognizable.

Human genomic diversity in Europe: a summary of recent research and prospects for the future

Gene frequencies in Europe are intermediate with respect to those of other continents. A phylogenetic tree reconstructed from 95 gene frequencies tested on 26 European samples shows some deviant populations (Lapps, Sardinians, Greeks, Yugoslavs, Basques, Icelanders and Finns) and other weakly structured populations. This behavior may have a simple interpretation: Europeans have not evolved according to a tree of descent probably because of the major role played by migrations in prehistorical and historical times. The leading component of the European genetic landscape is a gradient that originates in the Middle East and is directed to the northwest. According to the hypothesis by Ammerman and Cavalli-Sforza this gradient was generated by a migration of Neolithic farmers from Anatolia followed by continuous, partial admixture of the expanding farmers with local hunter-gatherers. Other leading components of the gene frequencies in Europe show correlations with possible movements of Uralic-speaking people and pastoral nomads from a region north of the Caucasus and Black Sea, which according to Gimbutas is the area of origin of Indo-European speakers. This analysis is based on classical pre-DNA genetic markers. The prospect of future research using DNA polymorphisms is discussed in the context of the Human Genome Project.

Carrier detection for prenatal diagnosis of hemophilia A in Italian families

BACKGROUND

The results obtained from a comparative analysis between phenotypic bioassays as the ratio of factor VIII: C clotting activity to factor VIII: C-related antigen, and DNA haplotypes from RFLP's TaqI/St14 and BclI/F8A in 12 hemophilia A (HeA) families are described.

METHODS

DNA from HeA patients and related at-risk women has been analyzed by Southern blotting with two probes: the intragenic F8A and the extragenic St14. Factor VIII: C coagulant activity was measured by a one-stage method, and the Factor VIII-related antigen (FVIII: RAg) was assayed with bidimensional electrophoresis. Linkage analysis was performed with the LINKAGE computer programs; in particular, the risks of carrying HeA were calculated using the MLINK program.

RESULTS

The observed heterozygosity for the flanking marker DXS 52 (TaqI/St14 RFLP) in combination with intragenic BclI/F8A polymorphism was 0.94. A statistically significant difference in frequency was detected at the DXS 52 locus (allele 4) in comparison with other Caucasian populations. Linkage analysis made it possible to combine the plasma bioassay values with the DNA marker haplotypes to determine the probability of carriership; 22 females at risk were investigated: 4 of them were identified as carriers and 18 were excluded. The risk of carrying hemophilia A for some women at risk in six families is reported.

CONCLUSIONS

This study compares a classic method and DNA analysis in genetic counselling for hemophilia A. In some cases the two methods may give different results when identifying carriers in at-risk families. From these data it is possible to conclude that DNA analysis combined with the phenotypic bioassays for carrier detection gives more information that the two analyses taken separately.

Vitamin E supplementation and oxidative status of peripheral blood mononuclear cells and lymphocyte subsets in hemodialysis patients

Increased oxidative damage to cell membrane constituents causes profound changes in the membrane cytoarchitecture and modifications of the membrane physiological properties, e.g., the ability to respond to hormonal stimuli. In uremic patients receiving intermittent hemodialysis, a metabolic block of the phosphate pentose shunt has been described. This leads to insufficient detoxication of the hydroxyl radicals formed within the cells and therefore to increased oxidative damage to the polyunsaturated fatty acid constituents of the cell membranes. Vitamin E is known to reduce this oxidative damage and its harmful effects. We studied vitamin E (alpha-tocopherol acetate) administration in 10 chronically uremic patients receiving intermittent hemodialysis for positive effects on cell membrane-receptor response. The patients were studied before and after treatment for the extent of oxidative damage in peripheral mononuclear cells and for response to monoclonal antibodies to specific markers of T-lymphocyte subsets. After vitamin E treatment, oxidative damage decreased, and the membranes of peripheral mononuclear cells contained greater amounts of some unsaturated fatty acids. This is in agreement with a modification of the membrane phenotype markers of T-lymphocyte subsets and seems to confirm in vivo that changes in membrane structure first induced by increased oxidative damage due to the blockage of the phosphate pentose shunt can be reduced by the antioxidant action of vitamin E, which significantly influences the expression of membrane determinants.

Infection after injury: association with blood transfusion

This study was undertaken to evaluate the association between red blood cell transfusions and infections in an easily stratified, homogenous group of injured adults. All received their initial transfusions upon arrival to the emergency department. Over 5 years, 390 uncross-matched trauma patients received type "O" red blood cells (RBCs) during initial resuscitation. One hundred fifty-four (39%) died within 7 days because of injuries sustained: 236 (61%) survived at least 7 days. Of these 236, clear differences could be seen between those receiving 6 or fewer or 7 or more units of RBCs. When adjusted for age, sex, and severity of injury (Champion Trauma Score, Injury Severity Score, TRISS), the risk of infection was higher in those receiving 7 or more units of RBCs. Similarly, risk of infection was related to units of RBCs transfused in a dose-related fashion. Blood transfusions should be avoided, if possible. Arbitrary "trigger points" for transfusions should be abandoned.

Kidney transplant monitoring by anti donor specific antibodies

Donor-specific anti-HLA antibodies were studied by cytotoxicity crossmatching (CTXM) and flow cytometry crossmatching (FCXM) in 117 kidney transplant candidates; the same study was carried out in 33 cadaver-donor kidney recipients, during the first 3 post-transplant months, for which donor cells were available. Pre-transport evaluation showed that 82.9% of subjects were CTXM negative/FCXM negative, 6.8% of patients were positive in both tests, and 10.3% were CTXM negative/FCCM positive. Post-transplant monitoring for donor-specific antibodies (Abs-DS) showed that nine recipients (27.3%) were FCXM positive; six of them were IgG+ and three IgM+. In comparing these results with the clinical course, a significant association between FCXM IgG+ and rejection episodes was observed (P < 0.01).

Multivariate analysis of the variables affecting left ventricular filling in normal subjects

Pulsed Doppler measurements of left ventricular filling (LVF), two-dimensional and M-mode echocardiograms were performed in 189 healthy subjects, in order to evaluate factors influencing LVF Doppler indexes in normal subjects. LVF Doppler indexes (peak E, peak A, peak E/peak A, deceleration rate of peak E (ED) were related by univariate and multivariate analyses with the following parameters: age, sex, heart rate, systolic and diastolic blood pressure, aortic root and left atrial dimensions, left ventricular mass index, left ventricular shortening fraction. The stepwise analysis showed that age by itself explained up to 18% of peak E variance, 50% of peak A variance, 61% of peak E/peak A variance and 25% of ED variance. The other variables entered into the regression, slightly improved the predictive power (less than 10%). In conclusion, age is the major independent factor affecting LVF in normal subjects, although other variables show significant correlation also after age adjustment.