The Diabetes Family Behavior Scale (DFBS) was designed to measure diabetes-specific family support. The purposes of this study were to refine the scale and to assess reliability and criterion validity in terms of relationship to metabolic control. The DFBS was administered to 321 children and adolescents with insulin-dependent diabetes mellitus (IDDM). Blood was drawn for determination of glycosylated hemoglobin (HbA1c). Based on an item-analysis procedure, the DFBS was revised to include 47 items with two subscales, one to reflect guidance-control and one to reflect warmth-caring. Acceptable internal consistency was found for the DFBS total score (.86), and for the guidance-control (.81) and warmth-caring (.79) subscales. There was a statistically significant relationship in the expected direction between DFBS total score and HbA1c (r = -.12, P < .03), and between the guidance-control subscale and HbA1c (r = -.17, P < .002).

Abstract. In women heterozygous for hypoxanthine guanine phosphoribosyl transferase deficiency, the activity of this enzyme in the erythrocyte is usually normal. In a key kindred two such obligate heterozygotes were also heterozygous for glucose-6-phosphate dehydrogenase types A and B. The AB genotype was confirmed in one by assay of skin fibroblasts. Erythrocytes were exclusively of type B. These observations suggest the clonal origin of the hematopoietic system in these women from a primordial cell line with a single active X chromosome.Patients with complete deficiency of the activity of the enzyme hypoxanthine guanine phosphoribosyl transferase (HGPRT) (E.C.2.4.2.8) present clinically with the Lesch-Nyhan syndrome, in which mental retardation, choreoathetosis, spastic cerebral palsy, and self-destructive biting occur along with hyperuricemia." 2 The disorder is transmitted as an X-linked recessive trait.' In accordance with the Lyon hypothesis, the female carrier of the gene should be a mosaic, in which there are two populations of cells, one in which the activity of HGPRT is normal and the other in which the activity of HGPRT is completely absent. This has been shown to be the case in clones of fibroblasts grown in cell culture after biopsy of the skin of mothers of boys with the disease. 5 If the inactivation of one of the X chromosomes in the female were a random process, the mean activity of an enzyme determined by the X chromosome in a series of mothers of deficient males should approximate 50 per cent of normal, unless there were some form of regulation after inactivation. However, assay of HGPRT activity in the erythrocytes of a group of obligate heterozygotes has indicated that activity is normal in virtually all of them.6 Similarly, in autoradiographic studies of hypoxanthine incorporation in lymphocytes of heterozygous females, Dancis and colleagues' found no evidence of mosaicism. Observations on a family in which there were two types of glucose-6-phosphate dehydrogenase (G6PD) (E.C.1.1.1.49) as well as two types of HGPRT indicate that in the hematopoietic system there is selection for the cell with normal activity of HGPRT.Materials and Methods. Fibroblast cultures were established following punch biopsy of the skin and carried in Eagle's minimal essential medium with 20% fetal calf serum.

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