Search PubMed⌕ Search

Biomedical subjects

I Barrai

Publications and source records attributed to I Barrai.

At least 73 records · Page 4Linked to original sources
PubMed1987

Biological performance in beta-thal heterozygotes and normals: results of a longitudinal comparison in a former malarial environment.

Families of beta-thal heterozygotes and of normals studied in 1956 by Silvestroni and Bianco in the small town of Berra near Ferrara were studied again in 1981-85. It was possible to compare mortality, fertility, and migration, in the two groups of heterozygotes and normals after the lapse of one generation. At the power of resolution of the sample available and of the methods used, no difference was visible. However, it was possible to establish the upper limits of the differences in average age at death and in average fertility at the 5% level of significance.

Age Factors↗
PubMed1986

Torus palatinus: a segregation analysis.

Segregation analysis of 99 sibships in 2 samples from Venezuela and Japan indicates that a torus palatinus is inherited in simple dominant fashion. The gene shows variable expressivity and penetrance close to 85%, without significant heterogeneity between the populations considered. No evidence of sporadic cases has been found.

Gene Frequency↗
PubMed1986

Population structure of eastern Sicily.

A sample of 465 persons from Eastern Sicily was studied for 11 red-cell enzymes, namely GLO, GPT, EsD, PGP, PGD, Dia, AcP, PGM, SOD, CAI and CAII. The allele frequencies were compared with those of other Italian populations and showed that the island is homogeneous with the mainland for these systems. The rate of heterozygosity was studied as a function of interparental distance; although high (0.77) the correlation did not reach significance.

Acid Phosphatase↗
PubMed1985

Estimation of inbreeding by isonymy in Iberoamerican populations: an extension of the method of Crow and Mange.

The method of isonymy for the estimation of inbreeding levels was extended to use the potentialities offered by the Iberoamerican surname system, in which a child inherits his surnames both from the father and the mother. Four possible types of isonymy were recognized between the family names of a husband-wife pair. It was found that, limited to simple consanguinity, the ratio between isonymy and the inbreeding coefficient of consanguineous individuals, starting from first cousins, is constant and equal to 16. Consanguinity levels were studied in four Venezuelan groups, Isla de Toas, Los Teques, Quibor, and Colonia Tovar, using genealogies, classical isonymy, and the extended method. It was found that, for Iberoamerican populations, the extended method is more precise than the classical method.

Consanguinity↗
PubMed1985

Segregation analysis of hemophilia A and B.

We analyzed a sample of 1,485 families with hemophilia A and B and with unknown diagnosis. The frequency of sporadic cases was estimated to be .166 and .078 for the two types of hemophilia, respectively. The sex ratio of mutation rates did not differ significantly from unity. The average age of maternal grandfathers of probands at birth of mothers with a single child, affected by hemophilia B, and of maternal grandfathers of probands at birth of mothers with more than one child affected by hemophilia B, was higher than the age in appropriate control groups.

Age Factors↗
PubMed1984

Beta-thalassemia in the Po Delta: selection, geography, and population structure.

The allele frequencies for beta-thalassemia for 51 localities in the province of Rovigo, and in 25 localities in the province of Ferrara, were studied. It was observed that in the province of Ferrara there is a significant cline of frequencies; these decrease from the coast of the Adriatic Sea toward the west. No such gradient was visible in Rovigo. It was advanced, also on the basis of geography documented by ancient maps, that in the province of Rovigo there were multiple foci of selection for the thalassemia gene, and that in the province of Ferrara selection was stronger in the Oriental part of the area. Examination of the isolation by distance model with these data showed that the Malécot-Morton model fits for the Ferrara data and geography, whereas it does not for Rovigo.

Alleles↗
PubMed1983

A model for differentiation.

A model is proposed, in which differentiation is attributed to colinearity between polymerase states and promotors. The promotors are considered the equal of ordinal numbers, and the state of a polymerase molecule is changed by the activity of the products of the gene it has transcribed. Introns are assumed to be involved in this possibility. Repeated sequences function as labels of chromosomes and chromosome regions, and interact with the diffusing RNA polymerase molecules aimed at a given class of promotors, increasing the speed of specific interactions. The possibility that a quantitative code, with a form of scansion, exists to order promotors as well as repeated sequences, is discussed. A correlation between the base sequence of repeats and promotors is predicted.

Base Sequence↗
PubMed1983

A new rare variant of the glyoxalase I system of the red cell: GLO-Sicily.

A fast variant of the red cell enzyme glyoxalase I was identified in a sample of 663 persons from Eastern Sicily; the allele was designated GLOSi. The gene frequencies for the common alleles GLO1 and GLO2 are not different from those observed in other southern Italian populations, and are in agreement with the hypothesis of a westward gene flow from Asia.

Alleles↗
PubMed1980

Possible indication of breast cancer risk through discriminant functions.

In the Ferrara province of Italy, a screening programme for the detection of breast cancer was initiated in 1965; by 1976, 21,120 women had been examined. The biologic history of the women participating in the program is routinely collected at registration. Several biological variables can be extracted from the history. We used 15 biologic variables in order to construct discriminant functions between women affected by breast cancer and a group of control women. It was found that four variables suffice to separate the group of the women with breast cancer from the control group, although with some degree of uncertainty. The theory was advanced that the individual values of a discriminant function may be associated with the risk of healthy women for developing breast cancer. Data collected after the construction of the discriminant function hint at such an association. We have attempted to calculate a discriminant value for healthy women participating in screening programs, so that those having a discriminant value below a given threshold may be considered at higher risk than those above the threshold. The women in the high-risk group may then be submitted to an appropriate examination schedule.

Adult↗
PubMed1980

Assessment of prospective genetic counseling in the Ferrara area.

A group of 613 heterozygotes for beta thalassemia (267 married, 346 unmarried) who were screened mostly at elementary school age, were identified and interviewed at the average age of 23.7 years to assess their knowledge of the heterozygous state and its implications. It was found that 83% recalled some information about their heterozygous state; only 60% had some information about the meaning of being heterozygous, and only 26% said they knew of some relationship between Cooley's anemia and the heterozygous state for beta thalassemia. In the married group, the proportion of those having married another carrier was in agreement with random mating expectations. It was concluded that there is ample room for improvement in the procedures of delivery of prospective genetic counseling at the population level in this area.

Adolescent↗
PubMed1980

Genetic counselling in beta thalassemia in Ferrara.

The effects of retrospective and prospective genetic counselling were studied in the Ferrara area, where the gene for beta thalassemia has polymorphic frequency. It was found that retrospective genetic counselling may have an effect in influencing the retrospective behaviour of couples who already have a child with Cooley's anemia. If the child is at a late birth order, reproduction may be terminated; if it is at an early birth order, it is continued, so that reproductive compensation takes place. In prospective counselling, given after population screening, it was found that the individuals identified as heterozygotes know, in a large percentage, what their state is and what its possible reproductive consequences are. However, it was found that the effect of such knowledge is not significant in influencing the marriage choice of heterozygotes.

Female↗
PubMed1978

Reproductive compensation in families segregating for Cooley's anaemia in Ferrara.

The reproductive performance of 100 families segregating for Cooley's anaemia was studied and compared to the performance of 127 control families. The control families were those of the sibs of the parents in the segregating families. No differences was found in the variables which might affect fertility and fecundity in control and thalassaemic families, although a different shape of the distribution of the number of births per family was found; the distribution had a higher variance in thalassaemics than in controls. The interval between the birth of a normal and an affected child is significantly longer than the interval between the birth of an affected child and a subsequent one. It was thought that these findings are indicative of reproductive compensation in families segregating for Cooley's anaemia, and of the moderate effect of the genetic counselling given to them.

Adult↗
PubMed1977

Population genetics in the province of Ferrara. I. Genetic distances and geographic distances.

The ABO and Rh systems of the population in 26 residential units in the province of Ferrara were studied to detect the effect of genetic drift on the differentiation of gene frequencies. Results obtained from principal components analysis and dendrograms were similar. A significant correlation between genetic and geographic distance was found. It was therefore hypothesized that in the area of Ferrara children born to parents originating from different communes were heterozygous at more loci than children born to parents originating from the same commune. It was also thought that it may be possible to use geographic distance between birthplaces of parents as an indicator of hybridity in their children.

ABO Blood-Group System↗
PubMed1977

Population genetics in the province of Ferrara. II. Survival of children with Cooley's anemia.

The demographic data of children with Cooley's anemia seen at the thalassemia center in Ferrara were analyzed. Survival was studied as a function of several variables, the most interesting being the distance between birthplaces of the parents of affected children. This distance was considered an indicator of genetic distance, and therefore an indicator of residual hybridity of the children. The significant regression of survival on interparental distance might be interpreted as an indicator of increased survival due to residual hybridity. The significant correlation of survival with expected hybridity supports this interpretation.

Child↗