3.9 Conclusion

In this lab, we explored the relationship between parental age and the number of de novo mutations in their gametes.

• We plotted the relationship between maternal/paternal age and DNM count. This visualization suggested that DNM count increases with age for both groups.
  
  
• We confirmed this hypothesis by using a linear model, which tests if additional years of age have a non-zero effect on the number of DNMs.
  
  
• The number of paternal DNMs seemed to increase more quickly with age than maternal DNMs. We confirmed this by comparing the 95% confidence intervals of the slopes of the two models.

One final question – let’s assume that there really is a difference between the effect of age on DNMs in male and female gametes. What biological reasons might be causing this difference?

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