Possibilities
If both mom and dad have dominant genes, they will pass those genes to their offspring, and the puppy will take up their behavioral traits and resemblance. And it’s a similar story if both mom and dad have all recessive genes.
If mom and dad have a mixture of dominant and recessive genes, there is a 75% likelihood that the puppy will take up the parents’ resemblance and 25% likelihood that the puppy won’t resemble any of the parents.
If either mom or dad has all dominant genes, the puppy will take up their traits and resemblance. If one of the parents has all recessive genes, the likelihood of the puppy resembling either parent is 50-50.
Meiosis includes recombination
Meiosis is the process by which the two copies (one from each parent) of your chromosomes are assorted into gametes (sperm or eggs). Imagine each pair of your chromosomes as a red and blue marble. Meiosis starts with the process of segregation. Using the marble example, segregation would be choosing one marble from each pair at random. That generates plenty of combinations of marbles, but what if we wanted even more variation, like multi-colored marbles or marbles of different sizes? That’s where recombination comes in.
Put simply, recombination is when the DNA content in a pair of chromosomes in a parent is shuffled before being passed onto their offspring. This shuffling occurs each and every generation to create additional genetic variation. This is how related puppies can look different from each other, and also why you and your sibling don’t look exactly alike.
Let’s take a closer look by examining the process from start to finish.
Dominant and Recessive Genes
As much as the 78 chromosomes are shared equally between the mom and dad, some genes are stronger than others. The stronger genes are referred to as Dominant Genes, while the weak ones are referred to as Recessive Genes. Due to their strength, the dominant genes overpower the recessive genes to determine the behavioral and physical traits that will be passed from the parents to a puppy. The recessive genes, on the other hand, remain passive. However, they are not all useless as they are still part of a puppy’s genetic make-up and can be passed to his offspring.
Mother Dog Reunited With Her Puppies All Grown Up | The Dodo Reunited
When two different purebred dogs have puppies, the resulting litter can have a wide spectrum of looks. This effect is compounded if the parents themselves are mixed breed. Sometimes it can be hard to believe the puppies are related going solely off their appearance. While it’s possible for one litter of puppies to have multiple fathers, the more likely explanation for different-looking siblings is the way genes are passed down to offspring during meiosis through segregation and recombination.