In her new book, Random Families: Genetic Strangers, Sperm Donor Siblings, and the Creation of New Kin, Wellesley College sociology and women’s and gender studies professor Rosanna Hertz offers timely insights into an unprecedented phenomenon: how the discovery of half-siblings sharing donor DNA who are born into different families has created enormous networks of genetic kin.

Co-authored with Margaret K. Nelson, professor of sociology emerita at Middlebury College, and released on November 7, Random Families examines the novel family ties resulting from the convergence of new, cutting-edge medical and social media technologies and the age-old human desire for social affinity and a sense of identity and belonging.

Over the last 30 years, advanced reproductive technologies such as IVF, sperm and egg donation, and surrogate carriers have enabled more and more individuals, whether single, partnered, gay, transgender, straight, or older, to conceive. More recently, the ubiquity and usability of DNA tests, donor registries, and social media platforms have helped donor families with shared genes find each other and, in some cases, establish contact and form close ties with one another, changing what was previously often an anonymous donor process and redefining what it means to be family.

“We are at a particular moment in history when the growth of donor-assisted conception, genetic testing, and shifting family structures have created new possibilities of kinship, and new ways to define and experience family relations,” said Hertz. “On the one hand, the popularity of online DNA ancestry sites reveals a public belief that genes define one’s identity, one’s looks, behavior, and personality, that genes create relatedness. On the other, donor families testify to a belief that kinship can be formed by choice. Our study examines how these two sets of cultural beliefs underlie, shape, and are shaped by the decisions and actions of individuals, and by the novel interactions that occur out of these unprecedented networks.”

Based on more than 350 interviews with parents and children (and donors linked to these family networks) from across the U.S., Random Families chronicles the diverse and complex choices individuals and families make at every step, as parents decide to conceive, select donors, and raise children; as adolescents curious about their roots consider contacting biologically related strangers; as Facebook networks and online registries of siblings of a single donor, sometimes numbering in the dozens, are formed; as connections are made between networks of strangers who happen to have the same genes.

Humanizing what has in the past been mostly an anonymous medical, legal, and economic transaction, the National Science Foundation-funded study raises new questions about the evolving modern family: Do shared genes make you family? Do donor-siblings, or “diblings,” have more than genes in common? How do children at different ages understand their relationships with their natal families and their genetic relatives? What becomes of the chance networks that arise once parents and donor siblings find one another?

Rosanna Hertz is the Class of 1919 50th Reunion Professor of Sociology and Women’s and Gender Studies at Wellesley College, where she researches issues related to families, work, and gender. She is the author of Single by Chance, Mother by Choice (2006), a path-breaking study of women who choose parenthood without marriage.

Read more about Hertz’s work at Oxford University Press.

About Wellesley College

Since 1875, Wellesley College has been a leader in providing an outstanding liberal arts education for women who will make a difference in the world. Its 500-acre campus near Boston is home to some 2,400 undergraduate students from 50 states and 83 countries.

Book Link: Random Families: Genetic Strangers, Sperm Donor Siblings, and the Creation of New Kin