MedGen

The disorder of congenital mirror movements (CMM) is characterized by early-onset, obvious mirror movements (involuntary movements of one side of the body that mirror intentional movements on the opposite side) in individuals who typically have no other clinical signs or symptoms. Although mirror movements vary in severity, most affected individuals have strong and sustained mirror movements of a lesser amplitude than the corresponding voluntary movements. Mirror movements usually persist throughout life, without deterioration or improvement, and are not usually associated with subsequent onset of additional neurologic manifestations. However, a subset of affected individuals with a heterozygous pathogenic variant in DCC may have CMM with abnormalities of the corpus callosum and concomitant cognitive and/or neuropsychiatric issues. [from GeneReviews]

Esophageal cancer, particularly esophageal squamous cell carcinoma (ESCC), is one of the most common cancers worldwide. Both environmental and genetic risk factors play a role in the pathogenesis of the disorder. In Europe and North America, heavy smoking, alcohol consumption, and increased body mass index (BMI) are the main environmental risk factors. In contrast, the particularly high incidence of ESCC in some areas of China, central Asia, and southern Africa is associated with nutritional deficiencies, high intake of nitrosamine-rich or pickled vegetables, and low socioeconomic status; smoking, alcohol consumption, and BMI play a lesser role in these populations. There is a tendency for familial aggregation of ESCC in high-risk geographic areas, suggesting a genetic component to increased susceptibility. Gastric cardia adenocarcinoma is another common type of cancer in China that shows similarities to ESCC in terms of geographic distribution and environmental risk factors (summary by Wang et al., 2010 and Abnet et al., 2010). Genetic Heterogeneity of Susceptibility to Esophageal Cancer See a variant in the ADH1B gene (103720.0001) for discussion of a possible genetic association with protection against squamous cell aerodigestive tract cancer, including esophageal cancer, in alcohol drinkers. See a variant in the ALDH2 gene (100650.0001) for discussion of a possible genetic association with increased risk for esophageal cancer in alcohol drinkers due to interaction between variants in the ADH1B and ALDH2 genes. See the S100A14 gene (607986) on chromosome 1q21 for a discussion of a possible association between variation in that gene and susceptibility to esophageal squamous cell carcinoma among smokers. Genetic Heterogeneity of Somatic Mutations in Esophageal Cancer Somatic mutations in several different genes have been found in esophageal cancer tissue. These genes include TP53 (191170), CDKN2A (600160), DEC1 (604767), DCC (120470), DLEC1 (604050), TGFBR2 (190182), LZTS1 (606551), RNF6 (604242), WWOX (605131), APC (611731), and RUNX3 (600210). [from OMIM]

Lynch syndrome is characterized by an increased risk for colorectal cancer (CRC) and cancers of the endometrium, ovary, stomach, small bowel, urinary tract, biliary tract, brain (usually glioblastoma), skin (sebaceous adenomas, sebaceous carcinomas, and keratoacanthomas), pancreas, and prostate. Cancer risks and age of onset vary depending on the associated gene. Several other cancer types have been reported to occur in individuals with Lynch syndrome (e.g., breast, sarcomas, adrenocortical carcinoma). However, the data are not sufficient to demonstrate that the risk of developing these cancers is increased in individuals with Lynch syndrome. [from GeneReviews]