WEINBERG, WILHELM

(b. Stuttgart, Germany, 25 December 1862; d. Tübingen, Germany, 27 November 1937), human genetics, medical statistics.

Weinberg was the son of Julius Weinberg, a Stuttgart merchant, and Maria Magdalena Humbert. Weinberg’s father was Jewish, and his mother was Protestant; both of his parents died early. Weinberg belonged to the Protestant faith as did his wife, Bertha Wachenbrönner, whom he married in 1896. They had four sons and one daughter. Weinberg studied medicine at the universities of Tübingen and Munich and obtained his M.D. in 1886. After clinical experience in Berlin, Vienna, and Frankfurt, he established himself in Stuttgart as a general practitioner and obstetrician (1889). For forty-two years he had a large private practice and also acted in public capacities as physician to the poor and to the socially insured. He attended more than 3,500 births, including more than 120 twin births.

Weinberg’s discoveries center around four areas: multiple births, population genetics, and ascertainment and medical statistics. His first important paper was the eighty-five-page “Beiträge zur Physiologie und Pathologie der Mehrlingsgeburten beim Menschen” (1901). In the article he established the difference method, which enabled him to derive the proportion of monozygotic and dizygotic twin births from statistical data on the sex combinations of otherwise undifferentiated twin births. He proceeded to discover differences between mono-and dizygotic twins in a variety of traits, including an inheritance of a twinning tendency for dizygotic but not for monozygotic twins.

When Weinberg became aware of Mendelism he asked himself “how different laws of inheritance would influence the composition of the relatives of given individuals.” Answers were provided in four extraordinary papers: “Über den Nachweis der Vererbung beim Menschen” (1908), “Über Vererbungsgesetze beim Menschen I and II” (1908-1909), and “Weitere Beiträge zur Theorie der Vererbung” (1910). Weinberg discovered the equilibrium law of monohybrid populations and the varied processes of attainment of equilibria in polyhybrid populations. He had become a founder of population genetics. The equilibrium law was also discovered slightly later by G. H. Hardy. It is now known as the Hardy-Weinberg law. In his studies of population genetics Weinberg’s derivations of the correlations between relatives expected under Mendelian heredity took into account both genetic and environmental factors. Indeed, he was the first to partition the total variance of phenotypes into genetic and environmental portions(1909, 1910).

Weinberg recognized early that different types of ascertainment may bias greatly the results of statistical inquiries. In “Über Methode und Fehlerquellen der Untersuchung auf Mendelsche Zahlen beim Menschen” (1912) he furnished methods of correction for various types of ascertainment. One such device is the sib method, in which correct proportions for traits are obtained by finding the ratio of affected to nonaffected traits among the sibs of the affected. Other methods also described by Weinberg are the proband and a priori methods.

Weinberg made detailed studies of mortality statistics and the statistics and genetics of specific diseases. He was the first to construct morbidity tables modeled after the long-known mortality tables.

Weinberg had no personal collaborators or students, although a few contemporary investigators were strongly influenced by him. Only in Weinberg’s later years did a new generation again begin to explore the areas in which he had achieved so much.

BIBLIOGRAPHY

I. Original Works. A bibliography of Weinberg’s numerous publications,most of which are journal articles, has been compiled by Eva R. Sherwood: it is on deposit in the biology library of the University of California at Berkeley and has been reprinted in Jh. Ver. Naturkde. Württemberg 118/119 (1964), 61–67.

II. Secondary Literature. An obituary (probably written by E. Rüdin) is in Archiv fur Rasen- und Gesellsclrnftsbiologie einschliessend Rassen-und Gesellschaftshygiene, 31 (1937), 54.

See also K. Freudenberg. “Wilhelm Weinberg zum 70. Geburtstage,” in Klinische Wochenschrift. 12 (1933), 46–47: E. Hübler, “Zum 100. Geburtstag von Wilhelm Weinberg,” Jh. Ver. vaterl, Naturkde. Württemberg 118/119 Jahrgang (1964), 57–67; F. J. Kallmann, “Wilhelm Weinberg. M. D.,,” in Journal of Nervous and Mental Diseases, 87 (1938), 263–264; H. Luxenburger, “Wilhelm Weinberg,” in Allgemeine Zeitschrift für Psychiatrie,107–109 (1938), 378–381; Curt Stern, “Wilhelm Weinberg, 1862-1937,” in Genetics, 47 (1962). 1–5; and “Wilhelm Weinberg. Zur hundertjährigen Wiederkehr seines Gebutsjabres,” in Zeitschrift menschliche Vererbungs, und Konstitutionslehre,36 (1962), 374–382.

Curt Stern