LIFE09200604007 Tabish - Homi Bhabha National Institute

Results
Objective 4
To establish correlation between the phenotype (e.g., poor DNA repair capacity,
apoptosis) with the genotype (e.g., polymorphisms in the genes)
4.4.1 Genotype-phenotype correlation
The probable effect of genotype combinations including total G Score, G
Score of DNA repair genes or MPN risk association signature was evaluated by
summing the number of adverse alleles across subgroups and comparing with
phenotypic responses after radiation and BPDE exposure (Fig. 39). Apart from total G
Score, G Score for only DNA repair genes, and MPN risk association signature, were
also correlated with the phenotype as the G Score of these subgroups had shown a
statistically significant difference between MPN patient and control subjects.
As the difference in the cell cycle profile after BPDE exposure was not
statistically significant between MPN and control groups, it was not correlated with the
genotype. To measure the strength of dependence between genotype and phenotype
method of Pearson correlation was used, when data followed a normal distribution or
Spearman correlation was used, when data did not follow normal distribution.
A comparison between total G Score and G Score of other subgroups with the
phenotypic response is shown in Table 14. The negative and positive value of
correlation coefficient indicated a negative or positive correlation between the genotype
and phenotype. A comparison of total G Score of all 22 SNPs, G Score of DNA repair
genes and MPN risk association signature showed a negative correlation with percent
cell death and percent G2 delay. This correlation was statistically significant for most
of the groups (Table 14, Fig. 40). While a positive correlation was observed between G
Score (all three groups) and percent γ-H2AX positive cells at 4 h time point, although it
was not significant.
131