Environmental Factor, November 2005, National Institute of Environmental Health Sciences
Panel Analyzes Feasibility of Twin Registry
By Blondell Peterson
A panel of twin research and registry experts convened in a day-long meeting at Nottingham Hall Oct. 21 to help determine the feasibility of establishing a national U.S. twin registry. The panel also discussed establishing three smaller registries for twins with type 1 diabetes, systemic lupus erythematosus and multiple sclerosis. Scientists will use the resources to investigate genetic susceptibility and environmental influences in complex diseases.
The meeting was the first of three expert panel meetings to be held during an 18-month study. Pat Chulada and Perry Blackshear, both NIEHS scientists in the Office of Clinical Research, are conducting the study along with a team of experts assembled by Alpha Gamma Technologies, Inc. in Raleigh. The team includes Linda Corey and Lenn Murelle, two past co-directors of the Mid-Atlantic Twin Registry and Vani Vannappagari, an epidemiologist from AGTI.
In the first major objective of the study, scientists will estimate and describe the twin population in the U.S. in order to estimate the potential size and composition of a national population-based registry. According to Chulada, there has been no systematic attempt to analyze the U.S. twin population to date, and this will be the first attempt to do so.
Based on vital statistics and other data, the AGTI team estimated there are approximately 5 million individual twins in the U.S., Chulada said. The team is further refining these statistics to include zygosity, age, gender, race and ethnicity, co-twin survival and other twin demographics, according to Chulada. Other objectives of the study are to develop optimal methods for ascertaining and enrolling twins, to conduct a cost-benefit analysis, and to investigate alternatives for creating or expanding U.S. twin resources, if a national U.S. twin registry is deemed feasible. Chulada said a second panel of experts will convene here in November to explore the ethical, legal and social climate for twin research and determine how this may impact methods used to identify twin pairs, and contact, recruit and collect data from them.
In the statement of work that facilitated the panel meeting, Chulada outlined how the NIEHS mission is a perfect environment for a twin study. The mission statement reads, "The mission of the NIEHS is to reduce the burden of environmentally associated disease and dysfunction by defining: 1) how environmental exposures affect our health; 2) how individuals differ in their susceptibility to these exposures; and 3) how these susceptibilities change over time.
"Twin studies can be powerful tools to isolate the genetic and environmental components of a disease," she said. "NIEHS would promote its mission by improving resources for twin studies. All institutes could benefit and would likely be interested in participating."