Leukocyte Telomere Length also known as Terminal Restriction Fragment Length

Terminal restriction fragment length was obtained by a blood draw at the time of the Offspring Clinic Exam 6.

Leukocyte Telomere Length (LTL) Analysis by the Terminal restriction Fragment Length (TRFL Analysis): A major problem with the LTL h analysis is that the DNA may migrate at slightly different rates in different regions of the gel. This is due to a host of technical reasons. For this reason, we have developed techniques that resolved each digested DNA sample and the molecular weight ladder on the same lane, thereby eliminating the effect of variation in DNA migration in different lanes. In this way, variation in DNA migrations in different lanes minimally affect the analysis.

In 1948, researchers recruited men and women from the town of Framingham, Massachusetts, beginning the first round of extensive physical examinations and lifestyle interviews that would later be analyzed for common patterns related to CVD development.

Initially, the Framingham Heart Study enrolled 5,209 men and women from the Framingham area who were between the ages of 28 and 62 years. Beginning in 1971, the Framingham Heart Study enrolled 5,124 men and women, who were either offspring of the original cohort or spouses of those offspring. In 2002, 4,095 third generation participants (men and women) were enrolled.

During each clinic exam cycle, the participants undergo a detailed examination including physical examination, medical history, laboratory testing, and electrocardiogram. Over the years, other tests (that may not be performed at every exam cycle) have included pulmonary function, lifestyle, physical function, cognitive function questionnaires, and various noninvasive cardiovascular tests including echocardiograms. The content of each exam cycle differs for Original, Offspring and Generation 3 cohorts and can be found in the Exam Cycle Protocol Manuals.

• Study Weblinks:
  • The Framingham Heart Study
• Study Design:
  • Prospective Longitudinal Cohort
• Study Type:
  • Longitudinal
• Total number of consented subjects: 1239
• Subject Sample Telemetry Report (SSTR)

The Original cohort began Exam 1 in 1948 (9/1948 - 4/1953) and has continued with biennial examinations to the present.

The Offspring cohort began Exam 1 in 1971 (8/1971 - 9/1975) and has on average been examined every 3 to 4 years since enrollment. However, there was an eight year window between exam 1 and exam 2. Exam 7 was performed from 9/1998 - 10/2001.

The Generation 3 cohort Exam 1 was performed 4/2002 - 7/2005.

Examinations continue to be performed.

• Primary Phenotype: Cardiovascular System

• Principal Investigator
  • Abraham Aviv, MD. New Jersey Medical School, Newark, NJ, USA.
• Institutions
  • The National Heart Lung and Blood Institute, National Institutes of Health, Bethesda, MD, USA.
  • Boston University, Boston, MA, USA.