What is the impact of CYP1A2 (Cytochrome P450 1A2) variants -163C>A and 5347C>T on melatonin functioning?

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From the Guidelines

Your CYP1A2 gene variants (-163C>A - C/A and 5347C>T - C/T) suggest you may have intermediate metabolism of melatonin, which is likely to impact your melatonin functioning in terms of duration and amplitude of melatonin production, as illustrated by the plasma melatonin profiles in Figure 1C of the study by S Benloucif et al. 1.

To understand the implications of these variants, it's essential to consider how melatonin is metabolized and its typical production patterns. The CYP1A2 enzyme, which is influenced by your genetic variants, plays a crucial role in melatonin metabolism in the liver. Given that you have heterozygous variants (one copy of each allele), your body likely metabolizes melatonin at a moderate rate, neither too quickly nor too slowly.

The study by S Benloucif et al. 1 provides insights into melatonin production patterns, showing that plasma melatonin levels typically peak between 04:00 and 08:00, with significant 24-hour rhythms. However, your intermediate metabolism might affect the duration and amplitude of your melatonin production.

For optimal melatonin functioning, considering your genetic profile, it might be beneficial to monitor your sleep patterns and adjust your lifestyle accordingly. Since your melatonin metabolism is intermediate, you may not need to take supplemental melatonin, but if you do choose to, starting with a standard dose and adjusting based on your response could be a prudent approach. Additionally, being mindful of factors like caffeine consumption, which competes with the same metabolic pathway as melatonin, is crucial for maintaining optimal sleep quality.

Key points to consider:

  • Intermediate melatonin metabolism due to CYP1A2 gene variants
  • Potential impact on duration and amplitude of melatonin production
  • Importance of monitoring sleep patterns and adjusting lifestyle
  • Caffeine consumption may impact sleep quality due to shared metabolic pathway with melatonin
  • Potential for adjusting melatonin supplementation based on personal response, if necessary.

From the Research

CYP1A2 Variants and Melatonin Functioning

The variants CYP1A2 -163C>A - C/A and 5347C>T - C/T are related to the CYP1A2 gene, which is responsible for metabolizing melatonin.

  • The CYP1A2 gene plays a crucial role in the metabolism of melatonin, with studies suggesting that melatonin is almost exclusively metabolized by CYP1A2 2, 3.
  • Variations in the CYP1A2 gene, such as the CYP1A2*1F polymorphism, can affect the metabolism of melatonin and may be used as a probe drug for CYP1A2 phenotyping 2, 3.
  • However, the specific variants mentioned (CYP1A2 -163C>A - C/A and 5347C>T - C/T) are not directly addressed in the provided studies.
  • It is essential to note that the provided studies focus on the relationship between CYP1A2 and melatonin metabolism, as well as the use of melatonin as a probe drug for CYP1A2 phenotyping 2, 3.
  • Other studies discuss the treatment of insomnia using cognitive behavioral therapy (CBT-I) and do not provide information on the specific variants mentioned 4, 5, 6.

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Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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