Curt Stern furthered the understanding of the mechanism of heredity and fundamentally contributed to establishing the relevance of genetic studies to medicine. Stern was born in Hamburg, Germany, and early in life he displayed a strong interest in natural history. His interest led him to enroll at the University of Berlin in 1920. Stern's doctoral studies in protozoology at the Kaiser Wilhelm Institute led to his receiving a Ph.D. in 1923, at the age of 21. At the time, he was the youngest person to receive a degree from the university.

After graduation, Stern changed research direction, having the opportunity to study Drosophila (fruit fly) genetics at Columbia University. Stern arrived at Columbia in 1924. In the next 12 years, he published several seminal papers detailing chromosomal-linked inheritance of physical characteristics and crossing-over of genetic material between chromosomes.

Due to return to Germany, Stern remained in the United States because of Hitler's rise to power and the implications for German Jews. After a short stint at Western Reserve University in Cleveland, Ohio, he moved to the University of Rochester, where he remained until 1947. From 1941 to 1947, Stern served as chairman of both the Department of Zoology and the Division of Biological Sciences. While at Rochester, Stern made fundamental contributions to Drosophila genetics. He discovered and coined the term isoallele, to describe the range of genetic variation possible from certain regions of the chromosome. In other research, Stern demonstrated the ability of low levels of radiation to induce genetic mutations via changes in the DNA.

In 1947, Stern joined the faculty of the University of California, Berkeley, where he became professor of zoology and, 11 years later, professor of genetics as well. Until his retirement in 1970, Stern investigated the genetic control of differentiation in Drosophila. Stern also contributed to human genetics by alerting physicians, through his three editions of the book Principles of Human Genetics, that indistinguishable phenotypes can have different genetic bases.

Stern received many honors and awards in recognition of his scientific achievements. In 1970, Stern was diagnosed with Parkinson's disease, which contributed to his death from cardiac failure eleven years later.