GENETIC AND ENVIRONMENTAL-INFLUENCES ON VOCATIONAL INTERESTS ASSESSEDUSING ADOPTIVE AND BIOLOGICAL FAMILIES AND TWINS REARED APART AND TOGETHER

The present investigation was a step toward a more thorough explicatio n of the amount of genetic and environmental variance in vocational in terests than has been found in past research. A comprehensive behavior al genetics research design was employed, using previously collected d ata from twins reared together, twins reared apart, adoptive families, and biological families. The data consisted of item responses from th e Strong Vocational Interest Blank/Strong Interest Inventory (SVIB/SII ). All of the data were scored using the Hansen Combined Form Scales f or the SVIB/SII (Hansen, 1982). Correlations were computed, and model fitting analyses were run to estimate additive genetic, nonadditive ge netic, shared environmental, and nonshared environmental effects. The results suggested that, on average, the variance in a wide range of vo cational interests can be attributed to 12% additive genetic and 24% n onadditive genetic effects and to 9% shared environmental and 55% nons hared environmental effects and measurement error. (C) 1994 Academic P ress, Inc.