Serum proteins in Down's syndrome

Serum albumin in Down Syndrome with and without Alzheimer's Disease

AIMS

We investigated whether or not serum albumin concentrations in Down Syndrome were lower than those of a cohort of similarly moderately- to-severely-disabled institutionalised patients without Down Syndrome and, if so, whether or not this could be ascribed to the presence of liver disease. We also sought to determine the influence of Down Syndrome, age, liver disease, and Alzheimer's Disease on the serum albumin concentration.

METHODS

We performed a cross-sectional study on 205 institutionalised patients with Learning Disabilities (47 with Down Syndrome, 158 without), and used multiple regression techniques to determine the relative effects of age, liver disease, and the presence or absence of Down Syndrome on the serum albumin concentration. Among Down Syndrome patients. We also sought to determine the association between serum albumin concentration and the presence of Dementia of Alzheimer's Type.

RESULTS

Down Syndrome patients had lower serum albumin levels than non-Down Syndrome patients. Serum albumin concentrations declined with age at a similar rate in both groups, such that the effect on serum albumin of having Down Syndrome was equivalent to an additional 44 years of age. The serum albumin concentration in Down Syndrome patients with Alzheimer's Disease was greater than that in Down Syndrome patients without Alzheimer's Disease.

CONCLUSIONS

Down Syndrome is associated with a low serum albumin concentration, independently of the presence of liver disease. The advent of Alzheimer's Disease in Down Syndrome is not associated with a further fall, and may be associated with a rise, in serum albumin concentrations.

Studies on the polymorphism of C3, Tf and Bg in Down's syndrome and other diseases

The distribution of phenotypes C3, Ff and Bg was investigated in sera of patients with Down's syndrome, oligophrenia, Wilson's disease and heart infarct. Quantitative determination of the concentration of C3 and C4 components of human complement was also carried out in these patients. The results are compared to healthy controls and are discussed with already reported data from other authors. Despite differences in the percentage distribution of various phenotypes in the patients' sera as compared to that of the controls, no statistically significant association could be established.

Serum and tissue proteins in tuberous sclerosis. I. Serum and red-cell polymorphic systems

5 serum protein polymorphic systems (haptoglobin, alkaline phosphatase, group-specific (Gc) proteins, beta2-glycoprotein 1 and leucine aminopeptidase) and 6 red-cell polymorphisms (adenosine deaminase, adenylate kinase, phosphoglucomutase, glutamic-pyruvic transaminase, phosphogluconate dehydrogenase and acid phosphatase) have been investigated in 54 subjects with tuberous sclerosis. The frequencies of all systems were compared with those of a control sample drawn from a similar mentally retarded population and abnormal distributions were detected in the haptoglobin and Gc system. Quantitative estimation of the serum levels of the Gc protein failed to detect any inter-group differences. Data on the deviations from the Hardy-Weinberg equlibrium, Haldane's Log ratio test between groups, and gene frequencies of both test and control groups are given. It is suggested that selection by mortality is the possible causation for the abnormal distribution of the Gc phenotypes, but the haptoglobin phenotype distribution requires further investigation with care being taken in the selection of control subjects.