In some types of ED, abnormal development of parts of the eye can result in dryness of the eye, cataracts, and vision defects. Professional eye care can help minimize the effects of ED on vision. Similarly, abnormalities in the development of the ear may cause hearing problems. Respiratory infections can be more common because the normal protective secretions of the mouth and nose are not present. Precautions must be taken to limit infections. Genetics
ED can be classified by inheritance (autosomal dominant, autosomal recessive and X-linked) or by which structures are involved (hair, teeth, nails and/or sweat glands). There are several different types with distinct genetic causes:

Hay–Wells syndrome (Rapp–Hodgkin syndrome) and EEC syndrome are all associated with TP63. Hypohidrotic ectodermal dysplasia can be associated with EDA, EDAR and EDARADD. Margarita Island ectodermal dysplasia is associated with PVRL1. Ectodermal dysplasia with skin fragility is associated with PKP1. Cloustons hidrotic ectodermal dysplasia is associated with GJB6. Naegeli syndrome/Dermatopathia pigmentosa reticulariss is associated with KRT14. Pachyonychia congenita is caused by multiple keratins. Focal dermal hypoplasia is associated with PORCN. Ellis–van Creveld syndrome is associated with EVC. Palmoplantar ectodermal dysplasia refers to several different conditions selectively affecting the hands and feet.
Micromastia (also called hypomastia, breast aplasia, breast hypoplasia, or mammary hypoplasia) is a medical term describing the postpubertal underdevelopment of a womans breast tissue. Just as it is impossible to define normal breast size, there is no objective definition of micromastia. Breast development is commonly asymmetric and one or both breasts may be small. This condition may be a congenital defect associated with underlying abnormalities of the pectoral muscle (as in Polands syndrome), related to trauma (typically surgery or radiotherapy) or it may be a more subjective aesthetic description. Self perceived micromastia involves a discrepancy between a persons body image, and her internalized images of appropriate or desirable breast size and shape. Societal ideals over breast size vary over time, but there exist many conceived ideas involving breasts and sexual attractiveness and identity across different cultures. Causes
Micromastia can be congenital or acquired disorder and may be unilateral or bilateral. Congenital causes include ulnar–mammary syndrome (caused by mutations in the TBX3 gene), Poland syndrome, Turner syndrome, and congenital adrenal hyperplasia. There is also a case report of familial hypoplasia of the nipples and athelia associated with mammary hypoplasia that was described in a father and his daughters. Acquired causes of micromastia include irradiation in infancy and childhood and surgical removal of prepubertal breast bud. Treatment
The procedure to remedy micromastia is breast enlargement, most commonly augmentation mammoplasty using breast implants. Other techniques available involve using muscle flap-based reconstructive surgery techniques (latissimus dorsi and rectus abdominis muscles), microsurgical reconstruction, or fat grafting.