What are the characteristics of X-linked dominant inheritance?

The emergence of genetic diseases is mainly directly related to our X chromosome. Hereditary nephritis, cataracts, syringomyelia, etc. are typical examples. Although X-linked dominant inheritance is relatively complex, it still has certain characteristics. Only by fully understanding it can we better understand this disease. So, what are the characteristics of X-linked dominant inheritance? Let's take a closer look at it.

① Regardless of gender, as long as the disease-causing gene is present, the disease will occur. However, because women have two X chromosomes, the incidence rate of women is higher than that of men. Because there is no normal chromosome to mask the disease, men tend to have more severe symptoms than women.

② One of the patient’s parents must suffer from the same disease (except for gene mutation).

③It can be inherited for several generations, but the patient’s normal children will not pass on the disease-causing genes to their offspring.

④Male patients pass the disease to their daughters but not to their sons, while female patients (heterozygotes) pass the disease to half of their sons and daughters.

Examples

In childhood, hereditary nephritis usually presents only with asymptomatic proteinuria or recurrent hematuria (may be visible hematuria in some cases), and rarely with hypertension. However, the disease continues to progress slowly, and men often die of chronic renal failure in young adulthood; women have milder symptoms and can reach a normal life span, but occasionally some patients develop uremia.

Some patients have sensorineural hearing loss; some patients have eye abnormalities such as cataracts, myopia or conical lenses, conical keratocones, nystagmus and spherical lenses. The pathogenic gene is located at Xq21.3～q24. However, hereditary nephritis has genetic heterogeneity, that is, it can also be inherited in autosomal dominant or autosomal recessive forms.

Other common X-linked dominant genetic diseases include: dark brown teeth, tooth enamel hypoplasia, pendulum-type nystagmus, oral, facial and finger syndrome, lipoma, syringomyelia, spinous follicular keratosis, vitamin D-resistant rickets, etc. In addition, most hereditary mental disorders (such as hereditary Alzheimer's disease, hereditary brain-intelligence gifted autism, etc.) are X-linked dominant genetic diseases.

The above is an introduction to the characteristics of X-linked dominant inheritance. I hope it will be helpful to everyone’s understanding. There are many types of diseases caused by X-linked dominant inheritance. In daily life, if there are similar diseases, you can test for X-linked dominant inheritance, which can help you understand the condition of your offspring, which is of great significance.