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Parallel Measurement of Circadian Clock Gene Expression and Hormone Secretion in Human Primary Cell Cultures
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Circadian rhythm of homocysteine is hCLOCK genotype dependent

Basil Paul1, K R Saradalekshmi, Ann Mary Alex

  • 1Human Molecular Genetics Laboratory, Rajiv Gandhi Centre for Biotechnology, Thiruvananthapuram, 695014, Kerala, India.

Molecular Biology Reports
|February 11, 2014
PubMed

Insights

Homocysteine (Hcy) levels exhibit daily rhythmicity, influenced by MTHFR and hCLOCK genes. This genetic link between Hcy and body time explains individual risk variability for cardiovascular and neurological diseases.

Area of Science:

  • Biochemistry
  • Chronobiology
  • Genetics

Background:

  • Homocysteine (Hcy) is a prognostic marker for neurological and cardiovascular diseases.
  • Hcy surges can increase cardiovascular events, and hemodynamic modulations link to chronotype.
  • Precise Hcy monitoring is crucial for risk evaluation.

Purpose of the Study:

  • Investigate Hcy rhythmicity under controlled diets.
  • Determine if Hcy rhythmicity is genetically controlled by circadian rhythm.
  • Explore the relationship between Hcy levels, chronotype, and specific gene variants.

Main Methods:

  • Screened 200 Malayalam-speaking individuals for MTHFR and hCLOCK gene variants.
  • Selected five subjects for detailed Hcy level monitoring.
  • Analyzed Hcy rhythmicity, considering gender, genotype, and chronotype.

Main Results:

  • Observed consistent Hcy rhythmicity with a morning nadir and evening peak in all subjects.
  • Found gender-specific Hcy level stratification among similar genotypes.
  • Identified variations in Hcy rhythmicity linked to MTHFR and hCLOCK genotype combinations, notably lower Hcy in hCLOCK rs1801260 CC genotype.

Conclusions:

  • Hcy levels and body time are genetically interdependent, explaining variability in Hcy.
  • Population-specific variations in MTHFR and hCLOCK genes suggest ethnicity-specific risk management strategies.
  • Genetic control of Hcy rhythmicity offers insights into disease risk.

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