Gene Role Disease OMIM Descriptions Sources
MCPH1 causing MCPH1 251200 The disease is caused by mutations affecting the gene represented in this entry. A disease defined as a head circumference more than 3 standard deviations below the age-related mean. Brain weight is markedly reduced and the cerebral cortex is disproportionately small. Despite this marked reduction in size, the gyral pattern is relatively well preserved, with no major abnormality in cortical architecture. Affected individuals are mentally retarded. Primary microcephaly is further defined by the absence of other syndromic features or significant neurological deficits due to degenerative brain disorder. Some MCHP1 patients also present growth retardation, short stature, and misregulated chromosome condensation as indicated by a high number of prophase-like cells detected in routine cytogenetic preparations and poor-quality metaphase G-banding. [read more] 12046007
15199523
16211557
MECP2 causing MRXS13 300055 The disease is caused by mutations affecting the gene represented in this entry. A disorder characterized by significantly below average general intellectual functioning associated with impairments in adaptative behavior and manifested during the developmental period. MRXS13 patients manifest mental retardation associated with other variable features such as spasticity, episodes of manic depressive psychosis, increased tone and macroorchidism. [read more] 10986043
11007980
11309367
11885030
12325019
12161600
11805248
12615169
16966553
MECP2 causing MRXSL 300260 The disease is caused by mutations affecting the gene represented in this entry. Increased dosage of MECP2 due to gene duplication appears to be responsible for the mental retardation phenotype. A disorder characterized by significantly below average general intellectual functioning associated with impairments in adaptative behavior and manifested during the developmental period. MRXSL patients manifest mental retardation associated with variable features. They include swallowing dysfunction and gastroesophageal reflux with secondary recurrent respiratory infections, hypotonia, mild myopathy and characteristic facies such as downslanting palpebral fissures, hypertelorism and a short nose with a low nasal bridge. [read more] 16080119
MED17 causing MCPHSBA 613668 The disease is caused by mutations affecting the gene represented in this entry. A disorder characterized by postnatal progressive microcephaly and severe developmental retardation associated with cerebral and cerebellar atrophy. Infants manifest swallowing difficulties leading to failure to thrive, jitteriness, poor visual fixation, truncal arching, seizures. There is no acquisition of developmental milestones and patients suffer from marked spasticity and profound retardation. Progressive microcephaly becomes evident few months after birth. [read more] 20950787
MED23 causing MRT18 614249 The disease is caused by mutations affecting the gene represented in this entry. A disorder characterized by significantly below average general intellectual functioning associated with impairments in adaptative behavior and manifested during the developmental period. [read more] 21868677
MEF2A causing ADCAD1 608320 The disease is caused by mutations affecting the gene represented in this entry. A common heart disease characterized by reduced or absent blood flow in one or more of the arteries that encircle and supply the heart. Its most important complication is acute myocardial infarction. [read more]
MERTK causing RP38 613862 The disease is caused by mutations affecting the gene represented in this entry. A retinal dystrophy belonging to the group of pigmentary retinopathies. Retinitis pigmentosa is characterized by retinal pigment deposits visible on fundus examination and primary loss of rod photoreceptor cells followed by secondary loss of cone photoreceptors. Patients typically have night vision blindness and loss of midperipheral visual field. As their condition progresses, they lose their far peripheral visual field and eventually central vision as well. [read more] 11062461
MKRN3 causing CPPB2 615346 The disease is caused by mutations affecting the gene represented in this entry. A condition defined as the development of secondary sexual characteristics in boys and girls at a chronological age that is 2.5 standard deviations below the mean age at onset of puberty in the population. Central precocious puberty results from premature activation of the hypothalamic-pituitary-gonadal axis. [read more] 23738509
MLXIPL WBSCR14 is located in the Williams-Beuren syndrome (WBS) critical region. WBS results from a hemizygous deletion of several genes on chromosome 7q11.23, thought to arise as a consequence of unequal crossing over between highly homologous low-copy repeat sequences flanking the deleted region. Haploinsufficiency of WBSCR14 may be the cause of certain cardiovascular and musculo-skeletal abnormalities observed in the disease. [read more]
MMP13 causing SEMD-MO 602111 The disease is caused by mutations affecting the gene represented in this entry. A bone disease characterized by moderate to severe metaphyseal changes, mild epiphyseal involvement, rhizomelic shortening of the lower limbs with bowing of the femora and/or tibiae, coxa vara, genu varum and pear-shaped vertebrae in childhood. Epimetaphyseal changes improve with age. [read more] 16167086