If the chi-square for the association of B7 with DRB1*0701-DRB4*0103102N is 48, what is a valid conclusion?

The conclusion that B7 is seen more frequently than expected with DRB10701-DRB40103102N is valid in light of the chi-square value of 48. The chi-square statistic is a measure used to determine the association between two categorical variables, and a high value, such as 48, typically indicates a significant deviation from what would be expected under the null hypothesis of no association. In this case, the presence of B7 is significantly more frequent in individuals with the specific DRB10701-DRB40103102N alleles than would be predicted by chance alone. This suggests a strong association or linkage between these genetic markers.

The chi-square value reflects the strength of this association, indicating that the occurrence of B7 in the presence of the specified DRB alleles is not merely coincidental but may have biological relevance in the context of immune response or disease association. The higher the chi-square value, the more pronounced the association; therefore, the conclusion that B7 is more frequently observed aligns with the statistical evidence provided by the chi-square analysis.