Concise memory formula

Out of nothing, it is recessive, recessive inheritance sees female disease, and father and son are sick as partners.

There is middle-aged inaction dominance, dominant inheritance to see male disease, mother and daughter disease as partners.

explain

Making something out of nothing is recessive: if parents are not sick and children are sick, it is a recessive genetic disease.

Recessive inheritance to see female diseases: if it has been diagnosed as recessive inheritance, find female patients.

Father and son have the same disease: if her father and son are both patients, it is recessive inheritance of X chromosome; As long as one of them is normal, it is autosomal recessive inheritance

There is a dominance of middle-aged inaction: if parents are sick and children are not sick, it is a dominant genetic disease.

Dominant inheritance to see male diseases: if it has been determined that it is a dominant genetic disease, find a male patient.

Mother and daughter are accompanied by illness: look at his mother and daughter, if they are both patients, they are accompanied by X chromosome dominant inheritance; As long as one of them is normal, it is autosomal dominant inheritance.

Extended data

Autosomal recessive genetic diseases are caused by recessive pathogenic genes located on autosomes, and their characteristics are as follows:

① The patient is homozygous for the pathogenic gene, and his parents are not necessarily sick, but they are all carriers (heterozygotes) of the pathogenic gene.

② About14 of the patients' brothers and sisters were sick, and the incidence of male and female patients was equal.

(3) There are no successive generations of inheritance in the family, and the parents, distant ancestors and collateral relatives of patients generally do not have the same patient.

(4) The incidence of offspring increases obviously when close relatives get married.

Generally speaking, there are 22 pairs of autosomes in each nucleus of human body, and there are countless gene fragments in the DNA of each pair of chromosomes. Each gene fragment consists of two genes. Genes are divided into dominant genes and recessive genes.

When a pair of genes are both dominant genes or one of a pair of genes is dominant and the other is recessive, then dominant traits are shown; And a pair of genes are recessive genes, showing recessive traits. However, general genetic diseases are recessive traits, so genetic diseases are negative forms of autosomes, which are manifested as genetic diseases.

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