What is the probability of inheritance of appearance from the previous generation

Intergenerational inheritance means that a child does not look like his or her parents in appearance or personality, but instead looks more like his or her grandparents. Of course, although skipping generations has a certain existence, its probability is relatively small, and there are certain differences in the skipping generations for different characteristics. Below, we will introduce you to the relevant knowledge about intergenerational inheritance in detail.

1. Appearance

"Hey, why do I look like my grandfather?" From a scientific point of view, it is very common for children to look like their ancestors. This is because the genes of the children's parents come from their ancestors and have a certain degree of inheritance. Moreover, after being arranged and combined again, some recessive genes become dominant genes. Therefore, it makes sense that the child's appearance would be very similar to his or her ancestors.

2. Skin color

Twins, one black and one white. According to the British Daily Mail, Kelly Hodgson, a girl from Nottingham, England, underwent a caesarean section and gave birth to a pair of twin girls, one black and one white. Kelly and her 17-year-old boyfriend Remi Hodder are both of mixed race, with their respective mothers being white and their fathers being black. Experts say the probability of mixed-race parents giving birth to "black and white twins" is only one in a million. This is a typical result of skipped generations.

3. Obesity

It has been found that overweight grandmothers influence the status of their grandchildren, increasing their risk of obesity. For example, if one of the grandparents is obese, the chances of their grandchildren being obese will increase. If both of your parents are obese, you must control your baby's weight from an early age to prevent obesity.

4. Genetic Diseases

Skip-generation genetic diseases, also known as sex-linked genetic diseases, are generally passed from grandfather to grandson, skipping the mother's generation, with obvious skip-generation inheritance phenomenon. In addition, all patients are male, so the disease is passed on to males but not females. Although females do not develop the disease, they are carriers of the pathogenic gene of sex-linked genetic diseases and pass the disease on to the males in their offspring.

Mental illness: Among the mental illnesses that are inherited from generation to generation, schizophrenia and manic-depressive disorder are the most likely to be inherited. A grandfather's illness may be passed on to his grandson.

Epilepsy: Primary epilepsy refers to epilepsy for which no cause can be found clinically and it has a certain degree of heredity. The general heritability is 3% to 5%. Among the relatives of primary patients, the closer the blood relationship, the higher the incidence rate, and vice versa. The age of onset of primary epilepsy is uncertain, and it usually begins in infancy and adolescence, with typical grand mal seizures or typical minor seizures as clinical manifestations.

Hemophilia: Hemophilia patients often have a family history, which manifests as "skip-generation inheritance". For pregnant women with a family history of genetic disease, prenatal diagnosis can be carried out through genetic testing to prevent problems before they occur and ensure the birth of a healthy baby.

Red-green color blindness: There are far more males than females suffering from red-green color blindness. If a normal woman marries a color-blind man, the father's color-blind gene can be passed on to their daughter via the X chromosome, but not to their son. The daughter then passes the color blindness gene from her father to her son, a phenomenon called cross-inheritance.