TaoMedAI/RareMedData huggingface dataset:
Marfanoid habitus-inguinal hernia-advanced bone age syndrome (ORPHA:314041)
A rare developmental defect with connective tissue involvement disorder characterized by tall stature, inguinal hernia, facial dysmorphism (including a long, triangular face, prominent forehead, telecanthus, downslanting palpebral fissures, bilateral ptosis, everted lower eyelids, large ears, long nose, full, everted vermilions, narrow and high arched palate, dental crowding), and radiologic evidence of advanced bone age. Additional manifestations include hyperextensible joints, long digits, mild muscle weakness, myopia, and foot deformities (i.e. hallux valgus, talipes equinovarus).
Marfanoid syndrome, De Silva type (ORPHA:2464)
A rare syndromic intestinal malformation characterized by the association of marfanoid features (including marfanoid habitus, severe myopia, retinal detachment, and mitral valve prolapse) with visceral diverticula (inguinal and/or femoral hernia and diverticula of the large and small bowel or urinary bladder). Some patients also had diaphragmatic eventration. There have been no further descriptions in the literature since 1996.
Marie Unna hereditary hypotrichosis (ORPHA:444)
A rare autosomal dominant hair loss disorder characterized by the absence or scarcity of scalp hair, eyebrows, and eyelashes at birth; coarse and wiry hair during childhood; and progressive hair loss beginning around puberty.
Epidemiology
Prevalence and incidence are unknown. To date, approximately 30 families and sporadic cases with a molecular diagnosis have been reported in the literature.
Clinical description
Affected individuals of both sexes are typically born with an absence or scarcity of scalp hair, eyelashes, and eyebrows. During early childhood the scalp hair becomes coarse and wiry. Loss of scalp hair begins around puberty in a pattern resembling that of androgenetic alopecia and progresses to almost total alopecia. Body, axillary, and pubic hair is sparse or absent as is beard hair in men and adolescent boys. No other ectodermal abnormalities are observed.
Etiology
The disorder is due to mutations in U2HR, an inhibitory upstream open reading frame of the HR gene located to 8p21.2, causing a gain of function of HR. Worldwide, about 20 different U2HR mutations have been identified in more than 30 affected families and sporadic cases. Recently, a missense mutation in EPS8L3, located on chromosome 1p13.2, was identified in a Chinese family; however, there are currently no other reports of this mutation.
Diagnostic methods
Diagnosis depends on clinical and microscopic examination and can be confirmed by mutational analysis of U2HR. Scanning electron microscopic study of the hair reveals irregular twisting, longitudinal ridging and cuticle peeling. Scalp biopsy shows a marked reduction in the number of follicles with follicular fibrosis. However, the small number of biopsies analyzed makes it difficult to obtain an objective impression.
Differential diagnosis
Differential diagnoses include hypotrichosis simplex, loose anagen syndrome, uncombable hair syndrome, ectodermal dysplasia syndromes, congenital atrichia, androgenetic alopecia and alopecia areata.
Genetic counseling
Transmission is autosomal dominant. Genetic counseling should be offered to affected individuals informing them that there is a 50% risk of having an affected child at each pregnancy.
Management and treatment
No curative treatment exists.
Prognosis
Life expectancy is normal but quality of life can be reduced due to the psychological impact related to the hair phenotype.

                            Last update: 
                            March 2021


                            - Expert reviewer(s): 
                            Pr Regina BETZ
Marshall syndrome (ORPHA:560)
A malformation syndrome that is characterized by facial dysmorphism, severe hypoplasia of the nasal bones and frontal sinuses, ocular involvement, early-onset hearing loss, skeletal and anhidrotic ectodermal anomalies and short stature with spondyloepiphyseal dysplasia and early-onset osteoarthritis.
Martinique crinkled retinal pigment epitheliopathy (ORPHA:466718)
A rare, genetic retinal disease characterized by characteristic "dried-out soil" fundus pattern due to diffuse deep white lines in the macula, to the level of the retinal pigment epithelium, which is slightly elevated and rippled. Macular exudation may be associated, and Bruch's membrane may be affected too. Occasionally, peripheral nummular pigmentary changes may be observed, associated with blindness. The lesions enlarge with time, with a preferential macular extension and confluence. Complications may include polypoidal choroidal vasculopathy, choroidal neovascularization or atrophic fibrous macular scarring that can lead to reduced visual acuity over time.
MASA syndrome (ORPHA:2466)
A X-linked, clinical subtype of L1 syndrome, characterized by mild to moderate intellectual disability, delayed development of speech, hypotonia progressing to spasticity or spastic paraplegia, adducted thumbs, and mild to moderate distension of the cerebral ventricles.
Mast cell sarcoma (ORPHA:66661)
Mast cell sarcoma is a rare, neoplastic disease characterized by locally destructive sarcoma-like growth of a solitary mass, composed of atypical mast cells, and without systemic involvement. It can affect any organ and the symptoms depend on the location. Cells are medium to large, pleomorphic or epithelioid, with oval, bilobed or multilobulated nuclei, sometimes prominent multinucleated giant cells. The disease closely resembles other neoplasms and may share associated markers, however the tumor is positive for mast cell tryptase.
Maternal hyperthermia-induced birth defects (ORPHA:2216)
A rare maternal disease-related embryofetopathy characterized by variable developmental anomalies of the fetus due to teratogenic effect of elevated maternal body temperature (resulting from febrile illness or hot environment exposure). Reported developmental anomalies include neural tube defects (spina bifida, ecephalocele, anencephaly), cardiac defects (transposition of great vessels), urogenital defects (hypospadias), abdominal wall defects, cleft lip/palate, eye defects (cataract, coloboma) or various minor anomalies (e.g., bifid uvula, preauricular pit or tag). Consensus regarding cause-effect relationship has not been reached.
Maternal riboflavin deficiency (ORPHA:411712)
Maternal riboflavin deficiency is a rare, genetic disorder of metabolite absorption or transport characterized by persistently decreased riboflavin serum levels due to a primary genetic defect in the mother and which leads to clinical and biochemical findings consistent with a secondary, life-threatening, transient multiple acyl-CoA dehydrogenase deficiency (MADD) in the newborn. The mother usually presents hyperemesis gravidarum in the absence of other features of riboflavin deficiency, such as skin lesions, jaundice, pruritus, sore mucous membranes, visual disturbances.
Maternal uniparental disomy of chromosome 1 (ORPHA:251009)
Maternal uniparental disomy of chromosome 1 is an uniparental disomy of maternal origin that most likely does not have any phenotypic expression except from cases of homozygosity for a recessive disease mutation for which only mother is a carrier.
Maternal uniparental disomy of chromosome 13 (ORPHA:97678)
Maternal uniparental disomy of chromosome 13 is an uniparental disomy of maternal origin that most likely do not have any phenotypic expression except from cases of homozygosity for a recessive disease mutation for which only mother is a carrier.
Maternal uniparental disomy of chromosome 16 (ORPHA:96185)
Maternal uniparental disomy of chromosome 16 is a uniparental disomy of maternal origin which might be associated with intrauterine growth retardation and an elevated risk of congenital malformations. Healthy carriers have also been reported. In addition, cases of homozygosity for a recessive disease mutation for which the mother was a carrier have been described, and specific phenotype depends on the inherited disorder.
Maternal uniparental disomy of chromosome 2 (ORPHA:96179)
Maternal uniparental disomy of chromosome 2 is an uniparental disomy of maternal origin that most likely does not have any phenotypic expression except from cases of homozygosity for a recessive disease mutation for which only mother is a carrier.
Maternal uniparental disomy of chromosome 20 (ORPHA:96186)
Maternal uniparental disomy of chromosome 20 (UPD 20) is a very rare chromosomal anomaly in which both copies of chromosome 20 are inherited from the mother. The main feature described is prenatal and postnatal growth retardation. Microcephaly, minor dysmorphic features and psychomotor developmental delay have been occasionally reported. Maternal UPD20 is most often ascertained by a mosaic trisomy 20 pregnancy.
Maternal uniparental disomy of chromosome 21 (ORPHA:96187)
A uniparental disomy of maternal origin that does not seem to have an adverse impact on the phenotype of an individual. There is a possibility of homozygosity for a recessive disease mutation for which the mother is a carrier and specific phenotype depends on the inherited disorder.
Maternal uniparental disomy of chromosome 22 (ORPHA:96188)
Maternal uniparental disomy of chromosome 22 is a uniparental disomy of maternal origin that does not seem to have an adverse impact on the phenotype of an individual. There is a possibility of homozygosity for a recessive disease mutation for which the mother is a carrier and specific phenotype depends on the inherited disorder.
Maternal uniparental disomy of chromosome 4 (ORPHA:96180)
Maternal uniparental disomy of chromosome 4 is an uniparental disomy of maternal origin that most likely does not have any phenotypic expression except from cases of homozygosity for a recessive disease mutation for which only mother is a carrier.
Maternal uniparental disomy of chromosome 6 (ORPHA:96181)
Maternal uniparental disomy of chromosome 6 is an uniparental disomy of maternal origin characterized by intrauterine growth retardation. Homozygosity for a recessive disease mutation for which only a mother is a carrier may lead to other phenotypes.
Maternal uniparental disomy of chromosome 9 (ORPHA:96183)
Maternal uniparental disomy of chromosome 9 is a uniparental disomy of maternal origin that most likely does not have any phenotypic expression except from cases of homozygosity for a recessive disease mutation for which only mother is a carrier.
Maternal uniparental disomy of chromosome X (ORPHA:261519)
A uniparental disomy of maternal origin that does not seem to have an adverse impact on the phenotype of an individual. There is a possibility of homozygosity for a recessive disease mutation for which the mother is a carrier and specific phenotype depends on the inherited disorder.
Matthew-Wood syndrome (ORPHA:2470)
A rare, genetic congenital malformation syndrome characterized by bilateral anopthalmia (or less commonly microphthalmia) in association with a variable combination of the following: pulmonary hypoplasia or agenesis, congenital diaphragmatic hernia or eventration, and variable cardiovascular defects (congenital heart defects and/or pulmonary artery atresia). Intellectual disability is noted in surviving patients. Other variable malformations affecting different organ systems, as well as facial dysmorphism, may be observed.
Maxillary arteriovenous malformation (ORPHA:141171)
Maxillary arteriovenous malformation is a rare vascular anomaly characterized by an abnormal connection of the arterial and venous vasculature, without capillary connections, in the maxillofacial area, usually presenting with chronic, intermittent, and potentially life-threatening, hemorrhage. Association with infection, pain, pressure, pulsation, swelling, facial asymmetry, headache, ocular pain, tinnitus, otalgia, epistaxis, toothache and/or teeth mobility and compressibility into their sockets is possible, although it may also be asymptomatic.
Maxillonasal dysplasia (ORPHA:1248)
A rare developmental anomaly characterized by midfacial hypoplasia affecting primarily the anterior part of the maxilla (premaxilla) and the nasal complex.
Epidemiology
Maxillonasal dysplasia (also called Binder syndrome) occurs in less than 1/10,000 birth but is probably underdiagnosed.
Clinical description
Affected individuals have very specific facial features that are easy to recognize. The central face is underdeveloped (midfacial hypoplasia), with an abnormally flat reduced nose, small crescent-shaped nostrils and a very short columella. The nasomaxillary angle is increased because of the missing anterior nasal spine, giving a ''heel of axe'' appearance at the lip-columella junction. The philtrum of the upper lip may be bow shaped, but without convergence to columella, demonstrating the non-adhesion of the orbicularis muscle to the anterior nasal spine. The anterior maxilla is underdeveloped with frequent lateral incisors anomalies ranging from small dystrophies to a total absence. These dental particularities lead to anterior malocclusion (class III) whereas the posterior occlusion remains normal. Fingers anomalies (such as hypoplasia of distal phalanges) can be present when the malformation is associated to a chondrodysplasia punctata.
Etiology
The etiology and pathogenesis of maxillonasal dysplasia remains uncertain.
Diagnostic methods
Diagnosis is suspected on clinical presentation. The absence of anterior nasal spine on radiological exam is pathognomonic of Binder.
Differential diagnosis
Phenocopies of maxillonasal dysplasia have been described in children exposed in utero to phenytoin or to vitamin K deficiency, being induced either by drug (anticoagulants) or by biliary lithiasis. Some authors consider maxillonasal dysplasia as an allelic form of chondrodysplasia punctata. Others suggest that it does not represent a distinct disease entity or syndrome, but rather is a nonspecific abnormality of the nasomaxillary regions. Holoproencephaly and arhinencephaly are the two main differential diagnosis, but there is no brain anomaly or olfactory deficit in maxillonasal dysplasia.
Antenatal diagnosis
Maxillonasal dysplasia can be suspected during second semester routine ultrasound. Nasal hypoplasia, flat nasofrontal angle, and midface hypoplasia are specific indicators.
Management and treatment
Surgery is the main treatment of the syndrome when required. Since the degree of malformation varies significantly between patients, surgical correction must be tailored individually. It can consist in orthognathic surgery and nose reconstruction. Orthodontic treatments and prosthodontic rehabilitations can also be performed.
Prognosis
Facial prognosis depends on the degree of malformation. Maxillonasal dysplasia can have a negative impact on quality of life.

                            Last update: 
                            April 2024


                            - Expert reviewer(s): 
                            Pr Joël FERRI  - Dr Adeline KERBRAT
Mayer-Rokitansky-Küster-Hauser syndrome type 1 (ORPHA:247775)
Mayer-Rokitansky-Küster-Hauser (MRKH) syndrome type 1, a form of MRKH syndrome (see this term), is an isolated form of congenital aplasia of the uterus and 2/3 of the vagina occurring in otherwise phenotypically normal females.
Epidemiology
MRKH syndrome (including type 1 and type 2) has a worldwide prevalence of 1/4500 live female births. The rate of MRKH syndrome type 1 varies largely between different cohorts reported, therefore an accurate incidence of this type is not possible.
Clinical description
MRKH syndrome type 1 is most often diagnosed in adolescence as the first symptom is most commonly a primary amenorrhea in young women presenting with otherwise normal development of secondary sexual characteristics and normal external genitalia. Patients lack the uterus and the upper 2/3 of the vagina. Because of this, difficulties with sexual intercourse have been reported. Pelvic pain can be reported in those with uterine remnants. As the uterus is missing or not functional, women cannot bear children. However, the ovaries are normal and functional.
Etiology
The exact etiology of MRKH syndrome remains largely unknown. Initially, MRKH syndrome was considered to be of sporadic occurrence, suggesting the involvement of non-genetic or environmental factors. However, no link between an environmental cause and MRKH syndrome has ever been established. It is now clear that MRKH syndrome has a genetic origin, through increasing family descriptions and numerous genetic studies already completed. The latter have led to reveal several chromosomal abnormalities associated with the disease, such as small interstitial duplications in 1q21.1 and in Xpter-p22.32, or deletions in 4q34-qter, 8p23.1, 10p14, 16p11.2, 17q12, 22q11.21 and Xq21.31. These genomic rearrangements affect numerous genes. Putative candidate genes have been described, such as  HNF1B  (17q12), LHX1 (17q12), SHOX (Xp22.33 and Yp11.32), TBX6 (16p11.2), and ITIH5 (10p14). The phenotype-genotype correlations however, have not been established.
Genetic counseling
MRKH syndrome (type 1 or type 2) was thought to be purely sporadic but in familial cases it seems to be inherited as an autosomal dominant trait with incomplete penetrance and variable expressivity. Genetic counseling can be beneficial in these familial cases.

                            Last update: 
                            January 2015


                            - Expert reviewer(s): 
                            Dr Karine MORCEL
Mazabraud syndrome (ORPHA:57782)
Mazabraud syndrome is a rare primary bone dysplasia (see this term) characterized by the association of fibrous dysplasia with intramuscular myxomas. Fibrous dysplasia (usually polyostotic, sometimes monostotic) occurs during the growth period and can be asymptomatic or can present with pain, skeletal deformities or fractures while intramuscular myxoma, associated with polyostotic fibrous dysplasia (see this term) is usually multifocal, typically occuring in the vicinity of skeletal lesions, and presents in adulthood as a painless soft-tissue mass (most commonly in the thigh). Although it is a benign condition, local recurrences of myxomas after incomplete excision and malignant transformation of a fibrous dysplastic lesion into osteogenic sarcoma have been reported.
McCune-Albright syndrome (ORPHA:562)
A rare mosaic syndrome characterized by the combination of two or more of the following: fibrous dysplasia of bone (FD), hyperpigmented macules, and hyperfunctioning endocrinopathies (precocious puberty, hyperthyroidism, growth hormone excess, endogenous Cushing syndrome).
Epidemiology
It is a rare disease with an estimated prevalence of between 1/100,000 and 1/1,000,000.
Clinical description
FD can involve a single or multiple skeletal sites and can present with a limp, pain, pathologic fracture, or craniofacial asymmetry. Scoliosis is common and may be progressive. In addition to precocious puberty (vaginal bleeding or spotting and early development of breast tissue in girls, testicular and penile enlargement and precocious sexual behavior in boys), other hyperfunctioning endocrinopathies may occur including hyperthyroidism, growth hormone excess, Cushing syndrome, and hypophosphatemia due to renal phosphate loss. Hyperpigmented macules usually appear in the neonatal period.
Etiology
The disease results from somatic variants of the GNAS gene, specifically in the cAMP-regulating protein, Gs alpha. The extent of the disease is determined by the proliferation, migration and survival of the cell in which the mutation spontaneously occurred during embryonic development.
Diagnostic methods
Diagnosis of McCune-Albright syndrome (MAS) is usually established on clinical grounds, based on the presence of two or more characteristic features. The evaluation of patients with MAS should be guided by knowledge of the spectrum of tissues that may be involved, with specific testing for each. Genetic testing is possible, but is not routinely available.
Differential diagnosis
Differential diagnoses include neurofibromatosis, osteofibrous dysplasia, non-ossifying fibromas, idiopathic central precocious puberty, and ovarian neoplasm.
Management and treatment
Treatment is dictated by the tissues affected, and the extent to which they are affected. Some forms of surgical interventions may be indicated for treatment of craniofacial and skeletal abnormalities associated with FD (progressive visual disturbance, severe pain, severe disfigurement), as well as in the management of MAS-associated endocrinopathies and malignancies. Bisphosphonates may be helpful for treatment of bone pain. Strengthening exercises are recommended to help maintain the musculature around the FD bone and minimize the risk of fracture. Treatment of all endocrinopathies is required.
Prognosis
Morbidity is proportional to the number and extent of tissues involved. Longevity is generally not affected. MAS is rarely associated with malignancy. Malignant transformation of FD lesions occurs in probably less than 1% MAS patients.

                            Last update: 
                            June 2024


                            - Expert reviewer(s): 
                            Dr Alison BOYCE  - Dr Michael COLLINS
McDonough syndrome (ORPHA:2471)
McDonough syndrome is a rare, multiple congenital anomalies/dysmorphic syndrome characterized by facial dysmorphsim (prominent superciliary arcs, synophrys, strabismus, large, anteverted ears, large nose, malocclusion of teeth), delayed psychomotor development, intellectual disability and congenital heart defects (e.g. pulmonic stenosis, patent ductus arteriosus, atrial septal defect). Additional features include thorax deformation (pectus excavatum/carinatum), kyphoscoliosis, diastasis recti and cryptorchidism. There have been no further descriptions in the literature since 1984.
McKusick-Kaufman syndrome (ORPHA:2473)
A rare, genetic multiple congenital anomalies syndrome characterized by genitourinary malformations (hydrometrocolpos in females and in males, glanular hypospadias and prominent scrotal raphe) , postaxial polydactyly that may affect only one or several limbs, and to a lesser extent cardiac defects. Hydrometrocolpos is due to either a congenital obstruction, imperforate hymen or vaginal atressia, and causes a palpable mass and possibly hydronephrosis. Other anomalies occasionally reported include choanal atresia, pituitary dysplasia, esophageal atresia and distal tracheoesophageal fistula, Hirschsprung disease, vertebral anomalies, and hydrops fetalis. The disorder is allelic with Bardet-Biedl, and as some phenotypic overlap has been observed, patients should be reevaluated in later childhood for retinistis pigmentosas and other signs of Bardet-Biedl syndrome.