Dysgenesis is an abnormal organ development during

embryo An embryo ( ) is the initial stage of development for a multicellular organism. In organisms that reproduce sexually, embryonic development is the part of the life cycle that begins just after fertilization of the female egg cell by the male sp ...

nic growth and development. As opposed to

agenesis In medicine, agenesis () refers to the failure of an organ to develop during embryonic growth and development due to the absence of primordial tissue. Many forms of agenesis are referred to by individual names, depending on the organ affected: ...

, which refers to the complete failure of an

organ Organ and organs may refer to: Biology * Organ (biology), a group of tissues organized to serve a common function * Organ system, a collection of organs that function together to carry out specific functions within the body. Musical instruments ...

to develop, dysgenesis usually implies disordered development or

malformation A birth defect is an abnormal condition that is present at birth, regardless of its cause. Birth defects may result in disabilities that may be physical, intellectual, or developmental. The disabilities can range from mild to severe. Birth de ...

and in some cases represents the milder end of a spectrum of abnormalities. Dysgenesis occurs during fetal development immediately after conception.

Classification

One of the first organs that is affected is the brain, this is known as cerebral dysgenesis. Dysplasia is a form of dysgenesis in adults that alters the size and shape of their cells that lead to abnormal development. One of the most common forms of dysgenesis is within the gonads. Examples: *

Gonadal dysgenesis Gonadal dysgenesis is classified as any congenital developmental disorder of the reproductive system characterized by a progressive loss of primordial germ cells on the developing gonads of an embryo. One type of gonadal dysgenesis is the devel ...

* Adrenal dysgenesis * Thyroid dysgenesis *

Anterior segment dysgenesis Anterior segment mesenchymal dysgenesis, or simply anterior segment dysgenesis, is a failure of the normal development of the tissues of the anterior segment of the eye. It leads to anomalies in the structure of the mature anterior segment, associa ...

Classification

References

Further reading