MedGen

Preeclampsia, which along with chronic hypertension and gestational hypertension comprise the hypertensive disorders of pregnancy, is characterized by new hypertension (blood pressure 140/90 or greater) presenting after 20 weeks' gestation with clinically relevant proteinuria. Preeclampsia is 1 of the top 4 causes of maternal mortality and morbidity worldwide (summary by Payne et al., 2011). Preeclampsia is otherwise known as gestational proteinuric hypertension (Davey and MacGillivray, 1988). A high proportion of patients with preeclampsia have glomerular endotheliosis, the unique histopathologic feature of the condition (Fisher et al., 1981). A distinct form of severe preeclampsia is characterized by hemolysis, elevated liver enzymes, and low platelets (HELLP syndrome) (Brown et al., 2000). Genetic Heterogeneity of Preeclampsia/Eclampsia Susceptibility loci for preeclampsia/eclampsia include PEE1 on chromosome 2p13, PEE2 (609402) on chromosome 2p25, and PEE3 (609403) on chromosome 9p13. PEE4 (609404) is caused by mutation in the STOX1 gene (609397) on chromosome 10q22. PEE5 (614595) is caused by mutation in the CORIN gene (605236) on chromosome 4p12. An association with PEE has been found with the EPHX1 gene (132810) on chromosome 1q. [from OMIM]

Alzheimer disease is the most common form of progressive dementia in the elderly. It is a neurodegenerative disorder characterized by the neuropathologic findings of intracellular neurofibrillary tangles (NFT) and extracellular amyloid plaques that accumulate in vulnerable brain regions (Sennvik et al., 2000). Terry and Davies (1980) pointed out that the 'presenile' form, with onset before age 65, is identical to the most common form of late-onset or 'senile' dementia, and suggested the term 'senile dementia of the Alzheimer type' (SDAT). Haines (1991) reviewed the genetics of AD. Selkoe (1996) reviewed the pathophysiology, chromosomal loci, and pathogenetic mechanisms of Alzheimer disease. Theuns and Van Broeckhoven (2000) reviewed the transcriptional regulation of the genes involved in Alzheimer disease. Genetic Heterogeneity of Alzheimer Disease Alzheimer disease is a genetically heterogeneous disorder. See also AD2 (104310), associated with the APOE*4 allele (107741) on chromosome 19; AD3 (607822), caused by mutation in the presenilin-1 gene (PSEN1; 104311) on 14q; and AD4 (606889), caused by mutation in the PSEN2 gene (600759) on 1q31. There is evidence for additional AD loci on other chromosomes; see AD5 (602096) on 12p11; AD6 (605526) on 10q24; AD7 (606187) on 10p13; AD8 (607116) on 20p; AD9 (608907), associated with variation in the ABCA7 gene (605414) on 19p13; AD10 (609636) on 7q36; AD11 (609790) on 9q22; AD12 (611073) on 8p12-q22; AD13 (611152) on 1q21; AD14 (611154) on 1q25; AD15 (604154) on 3q22-q24; AD16 (300756) on Xq21.3; AD17 (615080) on 6p21.2; and AD18 (615590), associated with variation in the ADAM10 gene (602192) on 15q21. Evidence also suggests that mitochondrial DNA polymorphisms may be risk factors in Alzheimer disease (502500). Finally, there have been associations between AD and various polymorphisms in other genes, including alpha-2-macroglobulin (A2M; 103950.0005), low density lipoprotein-related protein-1 (LRP1; 107770), the transferrin gene (TF; 190000), the hemochromatosis gene (HFE; 613609), the NOS3 gene (163729), the vascular endothelial growth factor gene (VEGF; 192240), the ABCA2 gene (600047), and the TNF gene (191160) (see MOLECULAR GENETICS). [from OMIM]

A stroke is an acute neurologic event leading to death of neural tissue of the brain and resulting in loss of motor, sensory and/or cognitive function. It is said to be the third leading cause of death in the United States. Gunel and Lifton (1996) noted that about 20% of strokes are hemorrhagic, resulting in bleeding into the brain. Ischemic strokes, resulting from vascular occlusion, account for the majority of strokes. Bersano et al. (2008) reviewed genetic polymorphisms that have been implicated in the development of stroke. Candidate genes include those involved in hemostasis (see, e.g., F5; 612309), the renin-angiotensin-aldosterone system (see, e.g., ACE; 106180), homocysteine (see, e.g., MTHFR; 607093), and lipoprotein metabolism (see, e.g., APOE; 107741). See also hemorrhagic stroke, or intracerebral hemorrhage (ICH; 614519). [from OMIM]