Skip to content

Genetic Susceptibility to Childhood Respiratory IIlness in Mexico City

Genetic Susceptibility to Childhood Respiratory Illness in Mexico City

Status
Completed
Phases
Unknown
Study type
Observational
Source
ClinicalTrials.gov
Registry ID
NCT00339521
Enrollment
2362
Registered
2006-06-21
Start date
1999-05-15
Completion date
2020-12-03
Last updated
2020-12-04

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Asthma

Keywords

Asthma, Mexico, Triads, Polymorphism, Genetic Predisposition

Brief summary

We propose to add a collection of genetic material to a clinical trial of anti-oxidant supplementation for the amelioration of asthma in 7-12 year olds being conducted at a public pediatric hospital in Mexico City. The anti-oxidant study has been approved by the Institutional Review Board of the National Institute of Public Health in Mexico City and is scheduled to begin in September 1998. The purpose of this add-on study is to examine genetic polymorphisms that may be related to asthma. Asthma cases will be compared with their parents as controls. In partaicular, we will save the buffy coat from the blood collection being done on the asthmatic child for measurements of plasma micronutrients in the anti-oxidant trial for extraction of DNA. This part of the sample would otherwise be discarded. In addition, we will enroll the parents of the asthmatic child as controls for the child. From the parents, either a 10 ml blood sample or if they prefer, a sample of buccal cells will be collected. Although our current plan is to compare the asthmatic child to the parents using statistical methods based on the transmission disequilibrium test because research into various family designs for candidate gene studies is rapidly evolving and various sibling control sample strategies have been discussed, we would also like to collect a genetic sample on as many of the child's siblings as possible with priority given to those closest in age. This will enhance the future usefulness of the samples. We anticipate enrolling approximately 200 families....

Detailed description

We propose to add a collection of genetic material to a clinical trial of anti-oxidant supplementation for the amelioration of asthma in 7-12 year olds being conducted at a public pediatric hospital in Mexico City. The anti-oxidant study has been approved by the Institutional Review Board of the National Institute of Public Health in Mexico City and is scheduled to begin in September 1998. The purpose of this add-on study is to examine genetic polymorphisms that may be related to asthma. Asthma cases will be compared with their parents as controls. In particular, we will save the buffy coat from the blood collection being done on the asthmatic child for measurements of plasma micronutrients in the anti-oxidant trial for extraction of DNA. This part of the sample would otherwise be discarded. In addition, we will enroll the parents of the asthmatic child as controls for the child. From the parents, either a 10 ml blood sample or if they prefer, a sample of buccal cells will be collected. Although our current plan is to compare the asthmatic child to the parents using statistical methods based on the transmission disequilibrium test because research into various family designs for candidate gene studies is rapidly evolving and various sibling control sample strategies have been discussed, we would also like to collect a genetic sample on as many of the child's siblings as possible with priority given to those closest in age. This will enhance the future usefulness of the samples. We anticipate enrolling approximately 200 families.

Interventions

None listed

Sponsors

National Institute of Environmental Health Sciences (NIEHS)
Lead SponsorNIH

Study design

Observational model
FAMILY_BASED
Time perspective
CROSS_SECTIONAL

Eligibility

Sex/Gender
ALL
Age
4 Years to 17 Years
Healthy volunteers
No

Inclusion criteria

* INCLUSION CRITERIA: Moderate to severe asthma, ages 7-12 and residing within 5 km of a particular ambient air pollution monitoring station.

Design outcomes

Primary

MeasureTime frameDescription
To create a resource to examine genetic susceptibility to asthma in Mexico City.End of StudyThe role of asthma candidate genes in the association between ozone exposure and asthma incidence.

Countries

Mexico

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026