Any Neu-Laxova syndrome in which the cause of the disease is a mutation in the PHGDH gene.

Hereditary angioedema-4 (HAE4) is an autosomal dominant disorder characterized by episodic subcutaneous or submucosal edema with onset usually in adulthood. Swelling most commonly involves the face and tongue, sometimes resulting in occlusion of the airway, which can cause death. The larynx, abdomen, and limbs may also be involved. Circulating C1 inhibitor (C1INH) levels and function, as well as plasminogen levels and activity, are normal. Although the disorder is autosomal dominant, there is evidence of incomplete penetrance, variable expressivity, and female predominance. The episodes may be triggered by stress, oral contraceptives, ACE inhibitors, and angiotensin II receptor blockades. The pathogenesis is believed to be due to altered plasmin function resulting in enhanced release of bradykinin. Successful clinical management has been achieved with tranexamic acid, which inhibits plasmin, and icatibant, a selective bradykinin B2 receptor (113503) antagonist (summary by Farkas et al., 2021). For a discussion of genetic heterogeneity of HAE, see 106100.

Hereditary angioedema-5 (HAE5) is an autosomal dominant disorder characterized by localized and self-limiting edema of the subcutaneous or submucosal tissue due to an episodic increase in vascular permeability. Affected individuals have onset of episodic swelling of the face, lips, hands, and abdomen in the second decade of life. Treatment with tranexamic acid may be effective in reducing the severity and frequency of the attacks (summary by Bafunno et al., 2018). For a discussion of genetic heterogeneity of hereditary angioedema, see 106100.

Hereditary angioedema-6 (HAE6) is an autosomal dominant disorder characterized by onset of episodic subcutaneous and submucosal swelling in adulthood. The face, mouth, and tongue are often affected; some patients have distal limb or abdominal edema. Levels of complement component inhibitor (C1INH; 606860) are normal (summary by Bork et al., 2019). For a discussion of genetic heterogeneity of HAE, see 106100.

Hereditary angioedema-7 (HAE7) is an autosomal dominant disorder characterized by onset of recurrent episodic swelling of the face, lips, and oral mucosa in the second decade. The disorder is due to abnormal vascular permeability (summary by Ariano et al., 2020). For a discussion of genetic heterogeneity of HAE, see 106100.

Hereditary angioedema-8 (HAE8) is an autosomal dominant disorder characterized clinically by recurrent and self-limited episodes of localized edema in various organs, including the face, tongue, larynx, and extremities. In rare cases, swelling of the tongue or larynx can lead to airway obstruction. Abdominal attacks may also occur, resulting in abdominal pain, vomiting, and diarrhea. The disorder results from enhanced vascular permeability (summary by Bork et al., 2021). For a discussion of genetic heterogeneity of HAE, see 106100.