Eating Disorders and Obesity: A Comprehensive Handbook

By Christopher G. Fairburn; Kelly D. Brownell | Go to book overview
Save to active project

Genetic Influences on Body Weight


How many overweight or obese individuals have developed their condition as a result of a major deficiency in one gene? How many are overweight or obese as a consequence of a strong genetic predisposition determined by DNA sequence variation at several genes? How many have only a slight genetic predisposition but have gained large amounts of body weight because they have poor nutritional habits and a sedentary lifestyle? How many do not have any genetic susceptibility but have nonetheless become overweight or obese? We cannot yet answer these questions, but in recent years, genetic epidemiology and molecular genetic studies have begun to generate data that allow us to formulate these questions in more relevant terms and to sketch some answers. This chapter examines the genetic epidemiology of the obesity epidemic. The molecular genetic issues are addressed in Chapter 5.


C. B. Davenport, from the Carnegie Institute, described in 1923 the first comprehensive attempt to understand the role of inheritance in human body mass for stature. Among his findings were that normal-weight parents sometimes have obese adult offspring, and that obese parents frequently have normal-weight adult descendants. In the aggregate, however, his study demonstrated that body mass index (BMI) values were more similar among family members than among unrelated persons.

Except for some rare Mendelian disorders, the vast majority of obese patients do not exhibit a clear pattern of Mendelian inheritance. Despite many studies on the familial aggregation and heritability of the obesity phenotypes, there is no unanimity among researchers regarding the importance of genetic factors.

Heritability is the fraction of the population variation in a trait (e.g., BMI) that can be explained by genetic transmission. It has been considered in a large number of twin, adoption, and family studies. The results depend on sampling strategy, sample size, and


Notes for this page

Add a new note
If you are trying to select text to create highlights or citations, remember that you must now click or tap on the first word, and then click or tap on the last word.
Loading One moment ...
Project items
Cite this page

Cited page

Citations are available only to our active members.
Sign up now to cite pages or passages in MLA, APA and Chicago citation styles.

Cited page

Bookmark this page
Eating Disorders and Obesity: A Comprehensive Handbook
Table of contents

Table of contents



Text size Smaller Larger
Search within

Search within this book

Look up

Look up a word

  • Dictionary
  • Thesaurus
Please submit a word or phrase above.
Print this page

Print this page

Why can't I print more than one page at a time?

While we understand printed pages are helpful to our users, this limitation is necessary to help protect our publishers' copyrighted material and prevent its unlawful distribution. We are sorry for any inconvenience.
Full screen
/ 632

matching results for page

Cited passage

Citations are available only to our active members.
Sign up now to cite pages or passages in MLA, APA and Chicago citation styles.

Cited passage

Welcome to the new Questia Reader

The Questia Reader has been updated to provide you with an even better online reading experience.  It is now 100% Responsive, which means you can read our books and articles on any sized device you wish.  All of your favorite tools like notes, highlights, and citations are still here, but the way you select text has been updated to be easier to use, especially on touchscreen devices.  Here's how:

1. Click or tap the first word you want to select.
2. Click or tap the last word you want to select.

OK, got it!

Thanks for trying Questia!

Please continue trying out our research tools, but please note, full functionality is available only to our active members.

Your work will be lost once you leave this Web page.

For full access in an ad-free environment, sign up now for a FREE, 1-day trial.

Already a member? Log in now.

Are you sure you want to delete this highlight?