Echinogenic action of L-alpha-lysophosphatidylcholine in Duchenne muscular dystrophy: a study on carrier detection.

The percentage of echinocytes induced after red cell treatment with L-alpha-lysophosphatidylcholine in the blood of 16 patients affected by Duchenne muscular dystropy (DMD) has been evaluated. Moreover, 15 mothers, 10 sisters, and 15 fathers were also included in the study. We found an increased level of echinocytes in dystrophic patients and in known and possible carriers. Correlations were also evaluated between echinocytes and serum enzymes used in DMD diagnosis, showing an increase of echinocytes also in DMD carriers with normal levels of serum creatine kinase, lactate dehydrogenase, and aldolase. Our results suggest that the sensitivity of erythrocytes to L-alpha-lysophosphatidylcholine in DMD could be used as a diagnostic test for carrier detection.

Frequency of qh+ chromosomal variants in a) radioexposed, b) Down syndrome and c) control subjects.

"Paranormal" variants of human chromosomes, devoid of phenotypical effects (since what appears to vary is heterochromatic, non-genic DNA) are known to be heritable. Some very large variants (especially the qh+ variants on chromosomes 1 and possibly 16 and Y) were reported to be associated with increased reproductive pathology (sterility, fetal wastage, chromosomal aberrations). These variants are currently assessed by the C-band techniques; very large C-bands correspond to morphological alterations (elongation or deformation) of the chromosome. A study of qh+ morphological variants of chromosomes 1, 9 and 16 in 40 professionally radioexposed subjects, in 40 Down-syndrome patients and in 40 controls is reported, indicating that the frequency of each variant is lowest among controls, intermediate among professionally radioexposed subjects and highest among Down-syndrome patients. These findings, if confirmed, suggest a possible use of the qh+ variants as heritable indicators of chromosomal damage.

HLA and psoriasis (with or without arthropathy).

30 probands affected by psoriasis, with or without arthropathy, and their relatives were typed for HLA-A, -B and -C antigens. Association of HLA-B16 and HLA-B17 with psoriasis was confirmed. One third of probands was without any known HLA-A, -B, -C marker. Considering probands with at least one HLA-B marker, we found that 50% of their sibs carrying marker is affected and the remaining 50% is healthy. To explain the weak association observed, an attempt to propose a model is made: such a model postulate a gene interaction between the HLA marker gene and an hypothetic "Ps (Psoriasis susceptibility) gene". The model, described in detail in this work, tries to explain why a large part (1/3) of probands is affected even if they do not carry any HLA marker and why 50% of marker positive sibs of marker positive probands are healthy.

[Incidence of the 9qh+ variant in subjects with occupational exposure to radiation and in cases of reproductive pathology]. / Incidenza della variante 9qh+ in soggetti professionalmente radioesposti ed in casi di patologia reproduttiva.

The frequency of the 9qh+ variant was fond to be significantly increased (as compared to controls) in the following classes of subjects: R)professionally radioexposed individuals; P)patients with chromosomal aberrations; PP)parents of P; Cs)sterile or pluriabortive couples. While the increase of 9qh+ in P and PP individuals was already known, the findings in professionally radioexposed individuals and sterile or pluriabortive couples appear to be relatively new. Occurrence of 9qh+ might prove to be a useful indicator of chromosomal damage, while confirmation of these findings would entail stringent limitation of professional and diagnostic radioexposure.

[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.