Will the baby be healthy? What will we name them? And, perhaps the most fun to ponder: What will my baby look like? But with the help of modern science, parents can make some educated guesses about what their baby will look like when it comes to specific traits, such as height and eye color.
Although newborns may strongly resemble one parent or the other, they might also look like neither. This is probably not because of the milkman, but rather the result of complex polygenic traits being passed down. You and your partner each have 46 chromosomes, of which 23 will get randomly sorted into your individual egg and sperm cells.
When sperm and egg join, they each bring their unique mix of 23 chromosomes, creating a single cell with the necessary This cell divides over and over again, eventually forming a fetus. Every time a couple conceives another kid, the same process occurs, but the chromosomes get shuffled in a different way, a process scientists refer to as recombination.
And this makes all of your potential babies look different. What will your baby look like? This might be the first question that comes to mind once your pregnancy has been confirmed. There are, after all, many genetic traits to think about. The human DNA think of it as some sort of genetic currency is organized into shapes you may have seen in drawings and photos called chromosomes.
They resemble a somewhat wobbly letter X. Each person has 46 in total. Your baby will inherit 46 chromosomes, 23 from each parent. One pair is the sex chromosomes, known as the X and Y. They will determine the sex of your baby. The mix of genes present on chromosomes, approximately 30, of them , will, for example, determine:. Hair and eye color are each determined by a set of genes that dictate the combination of pigment. This can make the hair, eyes, and skin lighter or darker.
Start with family photo albums from both parents. There you can see what hair color is predominant, whether baldness skipped a generation, and if blue eyes showed up occasionally to brown-eyed parents.
Your baby inherits genes from both parents. Some of them will be dominant and some recessive. How does that apply to eye color? For example, if you have brown eyes and mostly everyone in your family has brown eyes, that points to a strong or dominant version of a brown eye color gene or set of genes.
Suppose the other parent has blue eyes and his or her extended family does, too. Your baby will likely have brown eyes because that color is usually dominant. The blue eye genes will not be lost, though. They can manifest down the road in your grandchildren, should a certain mix of genes from parents occur. Fun Fact: Why do some family members look alike and others don't at all? Kids share 50 percent of their DNA with parents and siblings, so there's room for variation.
Like many babies, our son was born with bluish-grayish-not-sure-what-color-that-is eyes. Unless a baby's eyes are very dark at birth, they'll typically change. Starr explains. Keep in mind that it will take at least six months before an infant's eye color stabilizes. At least two genes influence the shade that develops, and each can come in two forms, or alleles: one that has brown and blue versions, the other with green and blue versions.
Your baby's eye color will depend on the combo of alleles he inherits from you and your partner. If you have dark eyes and your partner's are light, Baby is likely to end up with dark eyes as well. The brown allele is dominant, so if he gets one, he'll develop chocolate eyes no matter what else is in his code. Still, even two brown-eyed parents can produce a light-eyed kid if they both carry recessive blue genes.
If there are blue eyes on both sides of the family tree, your peanut may get them too. AB Poll: Whom does your baby look like? As I learned with Jason, a newborn's measurements don't necessarily predict her future height and weight. Many factors can influence size at first, including a mom-to-be's diet and health conditions such as gestational diabetes , says W. Gregory Feero, M. More than genes code for height, and regardless of her initial numbers, your sweet pea will probably grow to her genetically predisposed stature.
But kids who have poor nutrition and little physical activity tend to be shorter despite their genetic potential, Dr. Starr says. How to predict your child's future height? To make a rough estimate for a girl, subtract 5 inches from Dad's height, then average that number with yours.
For a boy, add 5 inches to your height, then average that figure with Dad's. Or follow your kid's growth curve: "If she's consistently in the 50th percentile for height and weight, it's likely she'll be close to that as an adult," Begleiter says. Still, you can't be sure, so even if your kid has been in the 99th percentile for months, don't bank on her scoring a volleyball scholarship just yet.
Sometimes children end up looking exactly like Mom or Dad -- or a brother or sister -- and sometimes they don't resemble anyone in the family. What gives? Kids share 50 percent of their DNA with each of their parents and siblings, so there's plenty of room for variation. If your little one takes after you, he may have inherited a lot of your dominant genes along with recessive ones from you and your partner, Dr.
If siblings end up looking alike, the mix of genes they inherited was similar. Each of your kids may get instructions for different features: Your firstborn can have your lips, while your youngest gets Dad's. Keep in mind that development is a dynamic process, Dr. Scheiner says. In fact, your child's bone structure won't be set until he's in his 20s because so many genes are involved, including those for growth, bone development, and even fat deposits.
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