Other syndromes, such as FIG4 associated Yunis Varon syndrome (MIM 216340), acro-der-mato-ungual-lacrimal-tooth (ADULT) syndrome, TP63 associated limb mammary syndrome (MIM 603543), TBX3 associated ulnar syndrome (MIM 181450) and KCTD1 associated scalp-ear-nipple syndrome (MIM 181270) have  also been clinically observed. Ectodermal dysplasia
Ectodermal dysplasia is commonly associated with syndromic amastia. The symptoms of ectodermal dysplasia can be referred to abnormal development of several ectodermal-derived structure such as hair, teeth, nails and sweat glands. Other symptoms may include the inability to sweat, vision or hearing loss, missing or underdeveloped fingers or toes and maldevelopment of breast tissue. Genetic mutations may cause ectodermal dysplasia, and these genes can pass from parents to children. The most common case is the mutation of EDA1 gene which is in X chromosome, and this mutation results in X-linked form hypohidrotic ectodermal dysplasia (XLHED). There is strong association between amastia and XLHED. Over 30% male patients with XLHED have absent nipples. 79% female carriers decrease the ability of breastfeeding. This suggests people with amastia should have a comprehensive skin test to exclude this syndrome. Polands syndrome
Polands syndrome is a genetic disorder associated with abnormal breast development. The prevalence rate of this syndrome is approximately 1 in 20000 to 30000. Both chest wall and upper limb lost normal function, and this syndrome usually occurs unilaterally. Mild and partial forms of Polands syndrome are common, which often been undiagnosed because the clinical feature is only breast asymmetry and a horizontal anterior axillary fold, without severe symptoms.
Class IV (UK/NZ: class I)
Very potent (up to 600 times as potent as hydrocortisone)

Clobetasol propionate (Dermovate Cream/Ointment, Exel Cream)
Betamethasone dipropionate (Diprosone OV Cream/Ointment, Diprovate Cream)

Class III (UK/NZ: class II)
Potent (50–100 times as potent as hydrocortisone)

Betamethasone valerate (Beta Cream/Ointment/Scalp Application, Betnovate Lotion/C Cream/C Ointment, Fucicort)
Betamethasone dipropionate (Diprosone Cream/Ointment, Diprovate Cream, Daivobet 50/500 Ointment)
Diflucortolone valerate (Nerisone C/Cream/Fatty Ointment/Ointment)
Hydrocortisone 17-butyrate (Locoid C/Cream/Crelo Topical Emulsion/Lipocream/Ointment/Scalp Lotion)
Mometasone furoate (Elocon Cream/Lotion/Ointment)
Methylprednisolone aceponate (Advantan Cream/Ointment)
Halometasone 0.05%

Class II (UK/NZ: class III)
Moderate (2–25 times as potent as hydrocortisone) 

Clobetasone butyrate (Eumovate Cream)
Triamcinolone acetonide (Aristocort Cream/Ointment, Viaderm KC Cream/Ointment, Kenacomb Ointment)

Class I (UK/NZ: class IV)
Mild

Hydrocortisone 0.5–2.5% (DermAid Cream/Soft Cream, DP Lotion-HC 1%, Skincalm, Lemnis Fatty Cream HC, Pimafucort Cream/Ointment)

Allergy associations
The highlighted steroids are often used in the screening of allergies to topical steroid and systemic steroids. When one is allergic to one group, one is allergic to all steroids in that group. Group A
Hydrocortisone, hydrocortisone acetate, cortisone acetate, tixocortol pivalate, prednisolone, methylprednisolone, and prednisone

Group B
Triamcinolone acetonide, triamcinolone alcohol, amcinonide, budesonide, desonide, fluocinonide, fluocinolone acetonide, and halcinonide

Group C
Betamethasone, betamethasone sodium phosphate, dexamethasone, dexamethasone sodium phosphate, and fluocortolone

Group D
Hydrocortisone 17-butyrate, hydrocortisone-17-valerate, alclometasone dipropionate, betamethasone valerate, betamethasone dipropionate, prednicarbate, clobetasone-17-butyrate, Clobetasol-17 propionate, fluocortolone caproate, fluocortolone pivalate, fluprednidene acetate, and mometasone furoate

History
Corticosteroids were first made available for general use around 1950. See also
Topical medication
Glucocorticoid
Corticosteroid
Retrometabolic drug design


== References ==