The Project Talent Twin & Sibling Study (PTTS)


The 1960 Project Talent study included about 4,600 twins and 550 other siblings attending the same schools. All of the siblings who participated in Project Talent had never been linked to each other in analyses of the original Project Talent data because it was beyond computer capability at the time. In 2009, AIR began matching up siblings by last name, parents’ names, and address.

There are several other large twin studies in the U.S., but PTTS is the only one that began with a representative sample. It includes males and females from a wide range of ethnic and racial backgrounds from across the U.S. PTTS is the only twin study that includes siblings of twins and other siblings from the same communities.

PTTS New Research

In September 2013, we received funding from the National Institute on Aging (part of the U.S. National Institutes of Health) to conduct a survey with twins and their siblings who had been in the 1960 Project Talent study (Grant # R01-AG-043656). This is a joint project between AIR and the University of Southern California (USC). The lead researchers are Dr. Deanna Lyter Achorn at AIR and Dr. Carol Prescott at USC, along with many other researchers and project staff.

Our first task was to locate the approximately 5,200 twins and siblings of twins – some of whom had not participated in more than 50 years. By searching the National Death Index,, and other Internet sites, we were able to locate over 95% of these Project Talent participants. This includes about 20% of the sample who are now deceased – the expected number for people born in the early- to mid-1940s. One of the biggest reasons for being unable to locate people is not knowing women’s married names.

In June 2014 we began collecting information from Project Talent twins and their siblings by a mailed survey. The survey asked participants about their education and occupational histories, vocational and leisure activities, military service, health behaviors, demographics, family structure and health conditions. We also included a series of questions to determine if twin pairs who are the same sex (both male or both female) are identical or fraternal.

As of December 2014, we received surveys from about 65% of individuals who we believe we located. Although we would like to hear from more of you, this is a very impressive response, particularly from those who haven’t heard from us since the 1960s.

Through this research, we seek to answer such questions as:

  • Why do some people stay healthy into older age, while others decline in middle age?
  • How does work history influence later-life health?

We are seeking additional funding to include other siblings from the same schools in future studies.


What is special about studying twins and siblings?

Twin studies have been critical for identifying the role of genes in the development of physical health and behavioral traits such as cognition, personality, and interests. Studying siblings who are not twins helps answer questions about the importance of family factors, gender, and birth order on these characteristics.

PTTS includes twins/triplets and siblings of twins. With additional funding, PTTS will expand to include siblings in other families from the same schools and neighborhoods. This combination provides a unique opportunity to distinguish the effects of family environment from school and neighborhood effects. This is important because for many health conditions it is important to know how much of the difference between people is due to their genetics, how much is due to early family background, and how much to current lifestyle choices (such as diet, exercise or smoking). We can answer these questions by comparing the similarity of different types of sibling pairs (e.g., identical and fraternal twins, their siblings, and non-twin siblings).

I’m a twin or sibling of a twin, why haven’t you contacted me?

You may be one of the 5% we couldn’t locate, or it’s possible that we don’t know you’re a twin. Please let us know that you’re a twin by emailing or calling us with this information. You can also register with Project Talent. This doesn’t obligate you to participate in the research, but will allow us to contact you to invite you and to keep you updated with our annual newsletter. Our project toll-free phone number is 1-866-770-6077 and our email address is

I don’t have any twins in my family, but I’m interested in participating in the study of siblings or other research.

Great! Please register with Project Talent and let us know you’d like to participate.

How can I get more information about PTTS?

You can read or download our research report describing PTTS published in Twin Research and Human Genetics.

We are analyzing the data and will post information to the webpage as it becomes available. Please email us at [email protected] with any questions.