Does a man with a genetic disease always pass it on to his offspring? Not necessarily. Below are five genetic diseases that are passed down only to sons. If a man has one of these five genetic diseases, it is not advisable for him to have children.
I. Hemophilia
The patient lacked an important clotting factor—antihemophilic globulin—in his blood. When bleeding occurred due to trauma from any cause, the blood could not clot, ultimately leading to death from excessive bleeding. Currently, this protein is readily available, significantly reducing the mortality rate.
II. Hypertrophic Progressive Muscular Dystrophy
Onset typically occurs around age 4, and usually before age 7. The thigh muscles atrophy, the calves become thickened and weak, resulting in a waddling gait, and paralysis gradually develops over several years. Most patients die around age 20. Currently, there is no effective treatment.
III. Favism
Favism is an acute hemolytic anemia caused by eating fava beans. Patients lack glucose-6-phosphate dehydrogenase, resulting in poor red blood cell membrane stability. Favism can occur at any age, but is most common in children under 9 years old. Symptoms usually appear 1-2 days after eating fava beans. Mild cases resolve spontaneously within a week by ceasing fava bean consumption; severe cases present with severe anemia, yellowing of the skin, hepatosplenomegaly, and dark urine; in the most severe cases, death can occur. Statistics show that 90% of favism patients are male. Some individuals develop hemolytic anemia after taking primaquine, aspirin, or sulfonamide drugs, which are genetic diseases with the same cause as favism.
IV. Red-green color blindness
Because this disease is not life-threatening, there is a higher chance that both parents carry the disease-causing gene. This means that the next generation, especially females, could inherit one X chromosome carrying the gene from each parent, potentially leading to symptoms. However, statistics show that the incidence rate in men is 14 times higher than in women. This disease can affect young people's choices of careers and professions.
Fifth, congenital agammaglobulinemia, hereditary deafness, and hereditary optic nerve atrophy are also X-linked recessive genetic diseases.
There are no specific treatments for these diseases; prevention generally involves avoiding consanguineous marriage. Women with a family history of these genetic diseases or who have given birth to affected children should undergo diagnosis before becoming pregnant. Generally, only female fetuses are carried to avoid placing a burden on the family and society upon the birth of an affected child.
