An autosome is any chromosome that is not a sex chromosome. The members of an autosome pair in a diploid cell have the same morphology, unlike those in allosomal pairs, which may have different structures. The DNA in autosomes is collectively known as atDNA or auDNA.
A genetic disorder is a health problem caused by one or more abnormalities in the genome. It can be caused by a mutation in a single gene (monogenic) or multiple genes (polygenic) or by a chromosomal abnormality. Although polygenic disorders are the most common, the term is mostly used when discussing disorders with a single genetic cause, either in a gene or chromosome. The mutation responsible can occur spontaneously before embryonic development, or it can be inherited from two parents who are carriers of a faulty gene or from a parent with the disorder. When the genetic disorder is inherited from one or both parents, it is also classified as a hereditary disease. Some disorders are caused by a mutation on the X chromosome and have X-linked inheritance. Very few disorders are inherited on the Y chromosome or mitochondrial DNA.
Macrocephaly is a condition in which circumference of the human head is abnormally large. It may be pathological or harmless, and can be a familial genetic characteristic. People diagnosed with macrocephaly will receive further medical tests to determine whether the syndrome is accompanied by particular disorders. Those with benign or familial macrocephaly are considered to have megalencephaly.
Weissenbacher–Zweymuller syndrome (WZS), also called Pierre-Robin syndrome with fetal chondrodysplasia, is an autosomal recessive congenital disorder, linked to mutations in the COL11A2 gene, which codes for the α2 strand of collagen type XI. It is a collagenopathy, types II and XI disorder. The condition was first characterized in 1964 by G. Weissenbacher and Ernst Zweymüller.
Osteopetrosis, literally "stone bone", also known as marble bone disease or Albers-Schönberg disease, is an extremely rare inherited disorder whereby the bones harden, becoming denser, in contrast to more prevalent conditions like osteoporosis, in which the bones become less dense and more brittle, or osteomalacia, in which the bones soften. Osteopetrosis can cause bones to dissolve and break.
Alport syndrome is a genetic disorder affecting around 1 in 5,000-10,000 children, characterized by glomerulonephritis, end-stage kidney disease, and hearing loss. Alport syndrome can also affect the eyes, though the changes do not usually affect vision, except when changes to the lens occur in later life. Blood in urine is universal. Proteinuria is a feature as kidney disease progresses.
Alagille syndrome (ALGS) is a genetic disorder that affects primarily the liver and the heart. Problems associated with the disorder generally become evident in infancy or early childhood. The disorder is inherited in an autosomal dominant pattern, and the estimated prevalence of Alagille syndrome is 1 in every 30,000 to 1 in every 40,000 live births. It is named after the French pediatrician Daniel Alagille, who first described the condition in 1969.
Neuroacanthocytosis is a label applied to several genetic neurological conditions in which the blood contains misshapen, spiculated red blood cells called acanthocytes.
Hyperimmunoglobulinemia E syndrome (HIES), of which the autosomal dominant form is called Job's syndrome or Buckley syndrome, is a heterogeneous group of immune disorders. Job's is also very rare at about 300 cases currently in the literature.
Tyrosine-protein kinase transmembrane receptor ROR2, also known as neurotrophic tyrosine kinase, receptor-related 2, is a protein that in humans is encoded by the ROR2 gene located on position 9 of the long arm of chromosome 9. This protein is responsible for aspects of bone and cartilage growth. It is involved in Robinow syndrome and autosomal dominant brachydactyly type B. ROR2 is a member of the receptor tyrosine kinase-like orphan receptor (ROR) family.
SCARF syndrome is a rare syndrome characterized by skeletal abnormalities, cutis laxa, craniostenosis, ambiguous genitalia, psychomotor retardation, and facial abnormalities. These characteristics are what make up the acronym SCARF. It shares some features with Lenz-Majewski hyperostotic dwarfism. It is a very rare disease with an incidence rate of approximately one in a million newborns. It has been clinically described in two males who were maternal cousins, as well as a 3-month-old female. Babies affected by this syndrome tend to have very loose skin, giving them an elderly facial appearance. Possible complications include dyspnea, abdominal hernia, heart disorders, joint disorders, and dislocations of multiple joints. It is believed that this disease's inheritance is X-linked recessive.
Frank–Ter Haar syndrome (FTHS), also known as Ter Haar-syndrome, is a rare disease characterized by abnormalities that affect bone, heart, and eye development. Children born with the disease usually die very young.
Antley–Bixler syndrome is a rare, severe autosomal recessive congenital disorder characterized by malformations and deformities affecting the majority of the skeleton and other areas of the body.
Warsaw breakage syndrome is a rare genetic condition. Fewer than 10 cases have been reported by 2018. Its clinical manifestations affect several organ systems, and includes microcephaly and severe growth retardation among others.
XK aprosencephaly is an extremely rare congenital disorder characterized by the absence of the embryonic forebrain. Because the prosencephalon gives way to the cerebral cortex, survival with aprosencephaly is not possible outside utero. The external symptoms are similar to holoprosencephaly, a related disorder, including a smaller than normal head (microcephaly), small eyeballs (microphthalmia), a small mouth (microstomia), anal atresia, and abnormalities of the external genitalia, radius, nostrils, and pharynx (throat).
Dysosteosclerosis (DSS), also known as autosomal recessive dysosteosclerosis or X-linked recessive dysosteosclerosis, is a rare osteoclast-poor form of osteosclerosis that is presented during infancy and early childhood, characterized by progressive osteosclerosis and platyspondyly. Platyspondyly and other skeletal abnormalities are radiographic features of the disease which distinguish DSS from other osteosclerotic disorders. Patients usually experience neurological and psychological deterioration, therefore patients are commonly associated with delayed milestones.
Otofaciocervical syndrome, also known as Fara Chlupackova syndrome, are a small group of rare developmental disorders of genetic origin which are characterized by facial dysmorphisms, long neck, preauricular and/or branchial pits, cervical muscle hypoplasia, hearing loss, and mild intellectual disabilities. Additional findings include vertebral anomalies and short stature.
Cerebro-costo-mandibular syndrome is a very rare genetic disorder which is characterized by jaw/chin, palate and rib abnormalities.
Mandibulofacial dysostosis with microcephaly syndrome, also known as growth delay-intellectual disability-mandibulofacial dysostosis-microcephaly-cleft palate syndrome, mandibulofacial dysostosis, guion-almeida type, or simply as MFDM syndrome is a rare genetic disorder which is characterized by developmental delays, intellectual disabilities, and craniofacial dysmorphisms.
SOFT syndrome, also known for the name its acronym originates from: Short stature-onychodysplasia-facial dysmorphism-hypotrichosis syndrome, is a rare genetic disorder characterized by the presence of short stature, underdeveloped nails, facial dysmorphisms, and hair sparcity across the body. It is caused by homozygous, autosomal recessive mutations in the POC1A gene, located in the short arm of chromosome 3. Fewer than 15 cases have been described in the medical literature.
