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Polymorphisms within the angiotensinogen gene (GT-repeat) and the risk of stroke in pediatric patients with sickle

D C Tang1, R Prauner, W Liu

  • 1Molecular and Clinical Hematology Branch, NIDDK, National Institutes of Health, Bethesda, Maryland 20892, USA.

American Journal of Hematology
|January 5, 2002
PubMed

Insights

Genetic markers for stroke risk in sickle cell disease (SCD) are needed. This study found specific GT-repeat alleles in the angiotensinogen (AGT) gene significantly increase stroke risk in pediatric SCD patients.

Area of Science:

  • Hematology
  • Genetics
  • Pediatrics

Background:

  • Stroke is a major complication in sickle cell disease (SCD).
  • Current methods lack reliable molecular or genetic markers for predicting stroke risk in SCD patients.
  • Previous research suggested relative hypertension as a potential risk factor.

Purpose of the Study:

  • To investigate the association between GT-repeat polymorphism in the angiotensinogen (AGT) gene and stroke risk.
  • To identify potential genetic markers for stroke risk assessment in pediatric SCD.
  • To evaluate the impact of specific AGT gene GT-repeat alleles on stroke occurrence.

Main Methods:

  • A case-control study involving 63 pediatric patients with SCD (21 stroke cases, 42 controls).
  • Genotyping of the GT-repeat polymorphism within the AGT gene.
  • Statistical analysis to compare genotype and allele distributions between stroke and non-stroke groups.

Main Results:

  • Significant differences in AGT gene GT-repeat genotype distribution were observed between stroke and non-stroke SCD patients (chi(2) = 10.82, P < 0.05).
  • Carriage of GT-repeat alleles A3 and/or A4 in the AGT gene was associated with a four-fold increased risk of stroke (OR = 4, P < 0.05).
  • Attributable odds ratios for alleles A3 and A4 were 2.24 and 4.33, respectively (P < 0.005).

Conclusions:

  • GT-repeat polymorphism within the AGT gene is associated with stroke risk in pediatric patients with SCD.
  • The presence of AGT gene alleles A3 and/or A4 significantly elevates the relative risk of stroke.
  • AGT gene GT-repeat genotyping may serve as a valuable genetic marker for assessing stroke risk in SCD patients, pending validation in larger cohorts.

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