Genetic Component of Handedness

March 3, 2008 updated by: National Cancer Institute (NCI)

Mapping the Genetic Component of Hand-Use Preference

Some functions are generally controlled by the right side of the brain and others by the left. One of the most easily observed examples of this "lateral specialization" of the brain is handedness-that is, a person's preference for using either the right or the left hand. This study will try to determine how the genetic component of handedness is inherited. It will test the theory that a single gene is involved in determining handedness and will try to locate the gene.

Families with at least two left-handed siblings aged eight years or older and at least one right-handed parent are eligible to participate in this study.

The left-handed siblings and both parents will fill out a brief questionnaire on hand usage, obtain a tissue sample taken from inside the cheek, and return the questionnaire and the sample by mail to the study researchers. The tissue sample will be used for DNA gene mapping.

Participants will be given a kit and instructions for obtaining the sample, along with mailing envelopes. Cheek swab sampling basically involves using a small brush to gently brush a layer of cells off of the inner wall of the cheek and then dropping the brush tip into a preservative.

The information gained from this study may provide insight into aspects of brain development that can be of medical benefit in the future.

Study Overview

Status

Completed

Conditions

Detailed Description

The purpose of this protocol, based on the hypothesis that human hand-use preference (handedness) is largely dependent on the action of a single locus, is to collect samples allowing us to map a "handedness gene" via detection of linkage to any of eight potential candidate genes/regions or via a whole or partial genome scan. We calculate that a full 300 marker genome scan of 100 parents and sibling pairs (allowing linkage analysis at 10 cM resolution), or the equivalent amount of data from partial scans of 300 families, has a high likelihood of allowing us to map the proposed gene. Eligible families, consisting of pairs of left-handed siblings plus at least one right-handed parent, were identified during Phase I of this study in 1996-1998, with approval from the now-lapsed FCRDC IRB. In Phase II of this study, we have collected cheek swab samples for DNA isolation from members of 100 eligible families for use in the mapping studies. DNA samples will not be linked back to individuals but grouped under a random family code that links to a database with limited information, including hand use preference and family structure. In the next phase, we wish to map the locus from cheek swab samples we have on hand.

Study Type

Observational

Enrollment

1400

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

    • Maryland
      • Bethesda, Maryland, United States, 20892
        • National Cancer Institute (NCI)

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Child
  • Adult
  • Older Adult

Accepts Healthy Volunteers

No

Genders Eligible for Study

All

Description

INCLUSION CRITERIA:

Members of families meeting the following criteria are eligible to participate:

Have two left-handed siblings.

Have at least one right-handed parent with no other known left-handed first degree relatives.

EXCLUSION CRITERIA:

All members of a family may be excluded if the right-handed parents or the left-handed siblings will not participate.

Individuals in families whose left-handed siblings are under the age of eight are not eligible to participate.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start

March 1, 2000

Study Completion

April 1, 2006

Study Registration Dates

First Submitted

March 23, 2000

First Submitted That Met QC Criteria

March 23, 2000

First Posted (Estimate)

March 24, 2000

Study Record Updates

Last Update Posted (Estimate)

March 4, 2008

Last Update Submitted That Met QC Criteria

March 3, 2008

Last Verified

April 1, 2006

More Information

Terms related to this study

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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