[Interaction between the ABO and Rh-Hr blood group systems in pairs of monozygotic (MZ) and dizygotic (DZ) twins]. / Interazione tra i sistemi ABO e Rh-Hr nelle nascite gemellari MZ e DZ.

Previous studies have revealed significant deviations of twin pairs' blood group distributions. A comparison between monozygotic (MZ) and dizygotic (DZ) pairs in a sample of 688 twin pairs as to interaction between ABO and Rh indicates that the main contribution to total deviation comes from the MZ pairs, thus confirming a different behaviour of the two twin types in this respect.

[Interaction of the genes of progressive muscular dystrophy (PMD) and blood groups (ABO)]. / Interazione tra i geni delle distrofie muscolari progressive (D.M.P.) e dei gruppi sanguigni (ABO).

Verification of the hypothesis that the inheritance of the Progressive Muscular Dystrophies (PMD) may involve dispersed genes, throiugh the study of a sample of 105 patients revealed that 82% of the Duchenne type belong to blood group O, while 79% of the limb-girdle type belong to group A. The fact that the Duchenne gene is sex-linked while the ABO locus is on chromosome 9 confirms the "dispersed genes" hypothesis, with important implications for further research, for genetic counselin and possibly for prevention.

[Incidence of the qh+ varients in the karyotype of subjects occupationally exposed to ionizing radiations]. / Incidenza delle varianti qh+ nel cariotipo di soggetti esposti professionalmente a radiazioni ionizzanti.

The "qh+" variants in the human karyotype are generally held to be inherited and devoid of phenotypical effects, although more frequent in families with cases of chromosomal aberrations. The finding of an even higher frequency of apparent mosaicism for 9qh+ in the karyotype of individuals professionally exposed to radiation supports the hypothesis that the variant may be mutagen-induced, possibly reflecting a "first hit" in chromosomal damage. Further studies are under way to verify the hypothesis, in view of a possible use as an indicator of radiation damage and/or risk factor in genetic counseling.