title: Degree of genetic homozygosity and distribution of AB0 blood types among patients with spina bifida occulta and spina bifida aperta.
abstract: BACKGROUND
  Assuming that spina bifida (SB) is a genetically controlled disease, the aim of our study was to evaluate the degree of genetic homozygosity and the distribution of AB0 blood types among patients with SB occulta and SB aperta by the homozygously recessive characteristics (HRC) test.
  
  
  METHODS
  Our study included an analysis of the presence, distribution and individual combination of 15 selected genetically controlled morpho-physiological traits in a sample of 100 patients with SB (SB occulta N = 50 and SB aperta N = 50) and a control group of individuals (N = 100).
  
  
  RESULTS
  We found a statistically significant difference between the mean values for genetic homozygosity (SB 4.5 ±0.3; control 3.0 ±0.2, p < 0.001) and also differences in the presence of certain individual combinations of such traits. In 12 (80.0%) of the 15 observed characteristics, recessive homozygosity was expressed to a greater degree among the group of SB patients, while for 9 (60.0%) of the traits this level of difference was statistically significant (Σ(χ) (2) = 266.3, p < 0.001). There was no difference in average homozygosity of such genetic markers between groups of SB occulta and SB aperta patients, but the type of individual variation in the two studied groups significantly differed. In the group of patients with SB the frequency of 0 blood group was significantly increased while B blood group was significantly decreased.
  
  
  CONCLUSIONS
  Our results clearly show that there is a populational genetic difference in the degree of genetic homozygosity and variability between the group of patients with SB and individuals without clinical manifestations, indicating a possible genetic component in the aetiopathogenesis of spina bifida.
authors.affiliation: Physical Medicine and Rehabilitation Department, University Childrens Hospital, Belgrade, Serbia.
authors.forename: Dejan
authors.initials: D
authors.lastname: Nikolic
authors.forename: Suzana
authors.initials: S
authors.lastname: Cvjeticanin
authors.forename: Ivana
authors.initials: I
authors.lastname: Petronic
authors.forename: Biljana
authors.initials: B
authors.lastname: Jekic
authors.forename: Radivoj
authors.initials: R
authors.lastname: Brdar
authors.forename: Tatjana
authors.initials: T
authors.lastname: Damnjanovic
authors.forename: Vera
authors.initials: V
authors.lastname: Bunjevacki
authors.forename: Nela
authors.initials: N
authors.lastname: Maksimovic