Scientists have found that the competition among sperm cells to fertilize the egg is due to their individual DNA make-up.
The study of sperm behavior is the first to demonstrate that genetic differences can directly affect the swimming behavior of sperm cells. This may offer additional knowledge on the impact of abnormal sperm cells on offspring, notably birth defects.
The work focused on sperm cells in male fish, specifically cave fish, and identified behavioral and morphological characteristics potentially altering the sperm's chances in the race to fertilize the egg.
The researchers found that while the flagellar length was the same in both normal and mutated samples, the velocity of the mutated samples was greater than that of the normal samples.