CYP1A1 3801T>C polymorphism implicated in altered xenobiotic metabolism is not associated with variations in sperm production and function as measured by total motile sperm and fertilization rates with intracytoplasmic sperm injection

Fertil Steril. 2016 Aug;106(2):481-6. doi: 10.1016/j.fertnstert.2016.04.003. Epub 2016 Apr 23.


Objective: To evaluate the cytochrome P450 3801T>C polymorphism's frequency in relation to semen production, as determined by semen analysis parameters, and sperm function, as determined by fertilization rates with intracytoplasmic sperm injection (ICSI).

Design: Case-control study.

Setting: Academic-affiliated private practice.

Patient(s): This study included patients undergoing IVF from 2004 to 2014 grouped into categories based on semen analysis parameters performed at a single andrology laboratory. Cases were patients with total motile sperm (TMS) counts of ≤20 × 10(6). Frequency-matched controls were selected with TMS of >20 × 10(6).

Intervention(s): The 3801T>C polymorphism was identified using DNA from serum samples with real-time quantitative polymerase chain reaction.

Main outcome measure(s): CYP1A1 3801T>C polymorphism frequency in TMS groups and distribution in fertilization rate outcomes with ICSI.

Result(s): A total of 460 cases were identified with ≤20 × 10(6) TMS, and 489 age-matched controls with >20 × 10(6) TMS were selected across the study time frame. For those with <5 × 10(6) vs. >20 × 10(6) TMS there was no difference when comparing heterozygous (odds ratio [OR] 0.96; 95% confidence interval [CI] 0.66-1.40) or homozygous mutant (OR 1.33; 95% CI 0.52-3.20) with the wild-type patients. Additionally, no difference was seen when analyzing subgroups <5 × 10(6), 5-20 × 10(6), and >20 × 10(6) TMS in a similar fashion. Receiver operating characteristic (ROC) curve analysis did not find a significant TMS count based on presence of the polymorphism (area under the ROC curve = 0.51). There were 460 patients who underwent IVF/ICSI, and fertilization rates did not differ with presence of the polymorphism (area under the ROC curve = 0.50).

Conclusion(s): Allele frequency of the 3801T>C polymorphism does not correlate with semen production as determined by TMS counts or sperm function as determined by fertilization rates with ICSI. The use of neither semen analysis parameters nor fertilization rates with ICSI helps identify CYP1A1 polymorphism carriers.

Keywords: Fertilization; P450 3801T>C polymorphism; male infertility; total motile sperm.

MeSH terms

  • Adult
  • Area Under Curve
  • Biotransformation
  • Case-Control Studies
  • Chi-Square Distribution
  • Cytochrome P-450 CYP1A1 / genetics*
  • Cytochrome P-450 CYP1A1 / metabolism*
  • Female
  • Fertility
  • Gene Frequency
  • Genotype
  • Humans
  • Infertility, Male / enzymology
  • Infertility, Male / genetics
  • Infertility, Male / physiopathology
  • Infertility, Male / therapy*
  • Male
  • Middle Aged
  • Odds Ratio
  • Pharmacogenomic Variants*
  • Phenotype
  • Polymorphism, Single Nucleotide*
  • Predictive Value of Tests
  • Pregnancy
  • Pregnancy Rate
  • ROC Curve
  • Risk Factors
  • Sperm Count
  • Sperm Injections, Intracytoplasmic* / adverse effects
  • Sperm Motility*
  • Spermatogenesis*
  • Substrate Specificity
  • Treatment Outcome
  • Xenobiotics / metabolism*
  • Young Adult


  • Xenobiotics
  • CYP1A1 protein, human
  • Cytochrome P-450 CYP1A1