title: Common 677C-->T mutation of the 5,10-methylenetetrahydrofolate reductase gene affects follicular estradiol synthesis.
abstract: OBJECTIVE
  To investigate the influence of the 5,10-methylenetetrahydrofolate reductase 677C-->T mutation on the E(2) synthesis in human granulosa cells (GCs).
  
  
  METHODS
  In vitro cell culture study.
  
  
  METHODS
  Research laboratory of a university hospital.
  
  
  METHODS
  Follicular fluids (n = 139) and GCs (n = 66) were obtained from patients undergoing controlled ovarian hyperstimulation for IVF with or without ICSI.
  
  
  METHODS
  Granulosa cells were cultured for a total of 5 days. On day 3, the cells either were stimulated with recombinant (r-) FSH or r-LH (80 IU/L for 48 h) or were sham stimulated.
  
  
  METHODS
  Estradiol and protein content were measured in the pooled follicular fluids of each individual. At the end of each GC-culturing period, the concentrations of E(2) were measured in the supernatants of triplicate cultures by immunoassays. The 5,10-methylenetetrahydrofolate reductase 677C-->T genotype was determined by RFLP analysis.
  
  
  RESULTS
  The E(2)-protein ratio of homozygous T/T carriers was significantly lower compared with that of homozygous C/C individuals. Furthermore, basal and r-FSH- as well as r-LH-stimulated E(2) synthesis of GC obtained from homozygous T/T patients was significantly reduced, compared with GC from heterozygous C/T and homozygous C/C subjects.
  
  
  CONCLUSIONS
  Decreased E(2) in follicular fluid and decreased E(2) synthesis of GC from homozygous T/T individuals suggest that reduced follicular E(2) is a result of impaired E(2) production of human GC.
authors.affiliation: Department of Obstetrics and Gynecology, Division of Endocrinology and Reproductive Medicine, Grosshadern, Ludwig Maximilians-University, Munich, Germany.
authors.forename: Stephanie
authors.initials: S
authors.lastname: Hecht
authors.forename: Roman
authors.initials: R
authors.lastname: Pavlik
authors.forename: Peter
authors.initials: P
authors.lastname: Lohse
authors.forename: Ulrich
authors.initials: U
authors.lastname: Noss
authors.forename: Klaus
authors.initials: K
authors.lastname: Friese
authors.forename: Christian J
authors.initials: CJ
authors.lastname: Thaler
mesh_terms: D000328:Adult; D003596:Cytosine; D004958:Estradiol / Q000096:biosynthesis*; D005260:Female; D005298:Fertility / Q000502:physiology; D015571:Follicular Fluid / Q000502:physiology; D005838:Genotype; D006801:Humans; D007258:Informed Consent; D042965:Methylenetetrahydrofolate Reductase (NADPH2) / Q000235:genetics*; D008875:Middle Aged; D006080:Ovarian Follicle / Q000502:physiology*; D020641:Polymorphism, Single Nucleotide; D011446:Prospective Studies; D013941:Thymine; D055815:Young Adult
chemical_list: D004958:Estradiol; D003596:Cytosine; D042965:Methylenetetrahydrofolate Reductase (NADPH2); D013941:Thymine