[Bi-allelic genetic markers and the determination of family relationships]. / Marqueurs génétiques bi-alléliques et détermination des liens de parenté

A very useful index for the validation of family relationship by means of genetic markers is the proportion of males in the population whose phenotype makes paternity of a child of known phenotype impossible: the proportion often indicates probability of exclusion of paternity. It may be proved in the case of biallelic mendelian systems that this probility of exclusion of paternity may be modified by close relationship between the mother and father of the child or between the real father of the child and the presumptive father.

Indefinite storage of dried Gm and Km (Inv) antigens: (examination of bloodstains 33 years old).

We confirm the great stability of the A and B antigens in dried blood, and the markedly lesser stability of antigen H. We demonstrate that it is possible to determine the immunoglobulin groups Gm(1), Gm(10) and Km(1)--formerly Inv(1)--in bloodstains 29 to 33 years old.

Plasma protein and enzyme polymorphisms in Belgium.

We report the frequencies of the Hp, Tf, Gc, Gm, Km, Ag and C3 plasma groups, and of the AcP1, PGD, PGM1, AK1, ADA, s-GPT and EsD enzyme groups, and we list the rare variants we observed in a Belgian population samples from the Liège region.

Probability of paternity exclusion when relatives are involved.

In diagnosis of paternity by means of polymorphic markers, the proportion of men excluded on the basis of the phenotypes of the mother and child is the best index for controlling information. Its expected value, the probability of exclusion of a male chosen at random with respect to a random child-mother couple, calculated from gene frequencies of every genetic system, may be modified by a close relationship between the mother, the real father, and the presumptive father. The father and even more the brother of the mother, if he is the father of the child, diminishes the probability of exclusion of an individual chosen at random in the population, and if he is falsely accused, he has a higher probability of being excluded. On the other hand, the brother of the real father chosen at random in the population has the least chance of being excluded. The two different rules of exclusion are involved in the calculations, the first one being the more reliable.

Turtledove: a new source of P1-like material cross-reacting with the human erythrocyte antigen.

An antigen cross-reacting with the human blood group P1 has been discovered in turtledove's blood an egg-white. In egg-white, this P1 antigenicity is carried by a glycoprotein called ovomucoid, which is particularly rich in galactose residues and which has been successfully used to produce specific anti-P1 antibodies in rabbits.

[Transfusion of blood with HL-A type. A study with 2,380 donors (author's transl)]. / Transfusion de sang sélectionné sur base du phénotype HL-A. Estimation des possibilités offertes par une population de 2 380 donneurs

Patients receiving repeated transfusions sooner or later develop an anti-HL-A immunization. To prevent or to delay this immunization by transfusing "deleucocyted" blood appears in the long run, to be a vague hope. So, it became essential to use blood from donors typed for the HL-A system. In this study we have examined what would happen if a pool of 2,380 HL-A type donors were available for 110 recipients. Twenty five per cent of the recipients will have blood available from more than 5 donors with the same HL-A types as themselves, and 71% of them can receive blood from more than 5 donors sharing at least one antigen at each locus (and with no antigen known to be different between them).

Polymorphism of the third component (C3) of complement and of Transferrin (Tf) in Belgium.

The phenotypes of C3 and of Tf were determined in 818 and 576, respectively, unrelated individuals living in Liege. The gene frequencies observed are: (formula: see text) The application to disputed paternity cases and to the study of twins is discussed.

Identification of blood stains by non-genetic characteristics: the HBs antigen of viral hepatitis B.

In forensic cases, until recently, identification of biological stains was based on the use of genetic markers, such as blood groups. In this paper, we show that another acquired characteristic, even if not immutable during life, may afford similar possibilities. As an example, we have demonstrated that the HBs antigen, associated with the hepatitis B virus, can help in the identification of bloodstains. The requisite condition for using this new marker, is that not too much time should elapse between the time the biological stains are formed and the moment when victim and suspected individual are examined for comparison of their blood with the stain. We have shown that in a dried state, the HBs antigen is very stable for a least six months. In vivo, it persists for a few week to 6 or 7 years according to thecase. HBs antigen is a relatively rate factor, its frequency being 0.5%ew marker, is that not too much time should elapse between the time the biological stains are formed and the moment when victim and suspected individual are examined for comparison of their blood with the stain. We have shown that in a dried state the, HBs antigen is very stable for a least six months. In vivo, it persists for a few week to 6 or 7 years according to the case. HBs antigen is a relatively rate factor its frequency being 0.5% in the Belgian population; the frequency reaches 2 to 3% in the Mediterranean population who constitute most of the immigrants in Belgium.