muramidase and Diseases-in-Twins

The heritability of saliva protein concentrations was investigated in stored samples of clarified stimulated whole saliva from adult twins participating in a study of periodontal disease genetics. Saliva was obtained from 29 monozygous and 20 dizygous twin pairs. Visits were scheduled so that both twins in a pair donated saliva at the same time of day. Flow rate was determined, and frozen samples later assayed for lactoferrin, lysozyme, secretory IgA, total peroxidase, myeloperoxidase and total protein. Pairs were always assayed together. Within- and between-pair variances were used to estimate twin intraclass correlations. Pearson correlations were used to estimate associations between saliva variables and clinical indices of gingivitis, dental plaque, periodontal attachment loss, and probing depth. Significant genetic contributions to variance were seen for total protein, lactoferrin, and total peroxidase. Total protein showed a significant positive correlation with gingivitis. There were no other correlations with clinical indices, and intraclass correlations for saliva variables did not change after adjustment for gingivitis. Dizygous twin correlations were higher than monozygous twin correlations for flow rate, lysozyme, and secretory IgA. That may be an artefact due to small numbers of pairs. It seems unlikely that a common environmental factor would strongly affect saliva in twins living apart as adults. Present findings, taken as sib correlations, support a genetic contribution to saliva protein concentrations. Problems with the twin model in saliva might be resolved by longitudinal studies of large numbers of twins.

Topics: Adult; Aged; Diseases in Twins; Female; Gingivitis; Humans; Immunoglobulin A, Secretory; Lactoferrin; Male; Middle Aged; Muramidase; Periodontitis; Peroxidase; Peroxidases; Saliva; Salivary Proteins and Peptides; Secretory Rate; Twins; Twins, Dizygotic; Twins, Monozygotic

Two autopsy cases of cystic brain lesion in utero are reported. One of them was a donor infant of twin transfusion syndrome. The baby died immediately after birth and showed multicystic encephalomalacia in the distribution of the anterior cerebral artery. The second baby was a stillborn infant with thanatophoric dwarfism with associated chronic periventricular leukomalacia (PVL). It was suggested that the multicystic encephalomalacia and chronic PVL found in the first and second cases were caused by persistent circulatory disturbances in utero.

Topics: Cysts; Diseases in Twins; Encephalomalacia; Female; Fetal Diseases; Fetofetal Transfusion; Glial Fibrillary Acidic Protein; Histocytochemistry; Humans; Immunoenzyme Techniques; Male; Muramidase; Nerve Tissue Proteins; Pregnancy; S100 Proteins; Thanatophoric Dysplasia

Topics: Adolescent; Bone Marrow Cells; Cell Survival; Child; Cytogenetics; Diseases in Twins; Female; Humans; Leukemia, Myeloid; Leukocyte Count; Leukocytosis; Muramidase; Neutrophils; Periodicity