When giving birth to a son, is it the father’s genes or the mother’s genes?

Having a son is mainly determined by the father's genes. The gender of the fetus is determined by the combination of sex chromosomes. The mother supplies the X chromosome and the father supplies the X or Y chromosome. When the father supplies the Y chromosome, the fetus develops into a male.

There are 23 pairs of chromosomes in human body cells, one of which is a sex chromosome. The female sex chromosomes are an XX combination, and the male sex chromosomes are an XY combination. During the formation of germ cells, female eggs carry only the X chromosome, while male sperm may carry the X or Y chromosome. When the sperm carrying the Y chromosome combines with the egg, the fertilized egg formed is an XY combination, and the embryo will develop into a male. The sperm carrying the X chromosome combines with the egg to form an XX embryo, which develops into a female. Therefore, from a genetic perspective, the type of sex chromosomes carried by the father's sperm directly determines the gender of the fetus.

Although the mother can only provide the X chromosome, some studies have shown that the maternal reproductive tract environment may have a weak impact on the survival rate of sperm carrying different sex chromosomes. For example, an alkaline environment may be more conducive to the survival of Y chromosome sperm, but this effect is extremely limited. There are also theories that factors such as maternal age and nutritional status may change the probability of fertilization with both types of sperm, but these hypotheses have not yet been fully confirmed. It is currently recognized by the medical community that the gender of the fetus is still mainly determined by the type of sex chromosomes in the father's sperm.

During preparation for pregnancy, both husband and wife should maintain a healthy lifestyle and avoid exposure to harmful substances. A balanced intake of foods rich in zinc, folic acid and other nutrients can help maintain the function of the reproductive system. However, it should be noted that no scientific method can 100% guarantee the birth of offspring of a specific gender. Do not believe in folk remedies or engage in illegal gender selection. The gender of the fetus is the result of natural selection, and parents should treat it rationally. Ensuring the physical and mental health of pregnant women is the key to eugenics and eugenics.