Genetic changes are related to the following types of collagenopathy, types II and XI.

The system for classifying collagenopathies is changing as researchers learn more about the genetic causes of these disorders.The clinical features of the type II and XI collagenopathies vary among the disorders, but there is considerable overlap. Common signs and symptoms include problems with bone development that can result in short stature, enlarged joints, spinal curvature, and arthritis at a young age. For some people, bone changes can be seen only on X-ray images. Problems with vision and hearing, as well as a cleft palate with a small lower jaw, are common. Some individuals with these disorders have distinctive facial features such as protruding eyes and a flat nasal bridge.

Different people are affected very differently by this disease. The main manifestation is fluid-filled cysts that grow on the brain and can cause damage that varies depending on their location and severity. Symptoms may manifest early in infancy, or may manifest as late as adulthood. Symptoms associated with autosomal dominant porencephaly type I include migraines, hemiplegia or hemiparesis, seizures, cognitive impairment, strokes, dystonia, speech disorders, involuntary muscle spasms, visual field defects, and hydrocephalus.

The type II and XI collagenopathies are a group of disorders that affect connective tissue, the tissue that supports the body's joints and organs. These disorders are caused by defects in type II or type XI collagen. Collagens are complex molecules that provide structure, strength, and elasticity to connective tissue. Type II and type XI collagen disorders are grouped together because both types of collagen are components of the cartilage found in joints and the spinal column, the inner ear, and the jelly-like substance that fills the eyeball (the vitreous). The type II and XI collagenopathies result in similar clinical features.

Autosomal dominant porencephaly type I is a rare type of porencephaly that causes cysts to grow on the brain and damage to small blood vessels, which can lead to cognitive impairment, migraines, seizures, and hemiplegia or hemiparesis.

Phakomatosis pigmentovascularis is subdivided into five types:

- Type 1 PWS + epidermal nevus

- Type 2 (most common): PWS + dermal melanocytosis +/- nevus anemicus

- Type 3: PWS + nevus spilus +/- nevus anemicus

- Type 4: PWS + nevus spilus + dermal melanocytosis +/- nevus anemicus

- Type 5: CMTC (Cutis marmorata telangiectatica congenita) + dermal melanocytosis

They all can contain capillary malformation. Type 2 is the most common and can be associated with granular cell tumor. Some further subdivide each type into categories A & B; with A representing oculocutaneous involvement and subtype B representing extra oculocutaneous involvement. Others have proposed fewer subtypes but currently this rare entity is mostly taught as having five subtypes currently.

Phakomatosis pigmentovascularis is a rare neurocutanous condition where there is coexistence of a capillary malformation (port-wine stain) with various melanocytic lesions, including dermal melanocytosis (Mongolian spots), nevus spilus, and nevus of Ota.

Collagen, type II, alpha 1 (primary osteoarthritis, spondyloepiphyseal dysplasia, congenital), also known as COL2A1, is a human gene that provides instructions for the production of the pro-alpha1(II) chain of type II collagen.

Autoimmune polyendocrine syndrome type 1 symptoms and signs include the following:

- Hypoparathyroidism

- Hypogonadism

- Vitiligo

- Alopecia

- Malabsorption

- Anemia

- Cataract

- Adrenal hyperplasia

Kufs is a neuronal disease, meaning it affects the nervous system, specifically voluntary movement and intellectual function. Symptoms of Kufs can manifest anytime between adolescence and adulthood, however it usually appears around age 30.

There are two types of Kufs: Type A and Type B. Type A causes seizures, myoclonic epilepsy (muscle jerks), dementia, ataxia (compromised muscle coordination), tremors and tics, dysarthria (speech difficulties), confusion, and psychotic behaviour. Although similar to Type A, patients with Type B do not suffer from myoclonic epilepsy or dysarthria, and they do display changes in personality. It is occasional that patients present with skin disorders causing dryness, roughness, and scaliness. The skin symptoms specifically, are a result of Keratin buildup in the skin cells (see ‘Genetic Causes’ for more information). Regardless of the type, most Kufs patients do not survive more than 15 years after their symptoms have manifested.

Autoimmune polyendocrine syndrome type 1 (APS-1), also known as autoimmune polyendocrinopathy-candidiasis–ectodermal dystrophy/dysplasia (APECED), autoimmune polyglandular syndrome type 1, Whitaker syndrome, or candidiasis-hypoparathyroidism–Addison's disease syndrome, is a subtype of autoimmune polyendocrine syndrome (autoimmune polyglandular syndrome) in which multiple endocrine glands dysfunction as a result of autoimmunity. It is a genetic disorder inherited in autosomal recessive fashion due to a defect in the "AIRE" gene (autoimmune regulator), which is located on chromosome 21 and normally confers immune tolerance.

The specific problems produced differ according to the particular abnormal synthesis involved. Common manifestations include ataxia; seizures; retinopathy; liver fibrosis; coagulopathies; failure to thrive; dysmorphic features ("e.g.," inverted nipples and subcutaneous fat pads; and strabismus. If an MRI is obtained, cerebellar atrophy and hypoplasia is a common finding.

Ocular abnormalities of CDG-Ia include: myopia, infantile esotropia, delayed visual maturation, low vision, optic disc pallor, and reduced rod function on electroretinography.

Three subtypes of CDG I (a,b,d) can cause congenital hyperinsulinism with hyperinsulinemic hypoglycemia in infancy.

Infants with achondrogenesis, type 2 have short arms and legs, a small chest with short ribs, and underdeveloped lungs. Achondrogenesis, type 2 is a subtype of collagenopathy, types II and XI. This condition is also associated with a lack of bone formation (ossification) in the spine and pelvis. Typical facial features include a prominent forehead, a small chin, and, in some cases, an opening in the roof of the mouth (a cleft palate). The abdomen is enlarged, and affected infants often have a condition called hydrops fetalis in which excess fluid builds up in the body before birth. The skull bones may be soft, but they often appear normal on X-ray images. In contrast, bones in the spine (vertebrae) and pelvis do not harden.

Achondrogenesis, type 2 and hypochondrogenesis (a similar skeletal disorder) together affect 1 in 40,000 to 60,000 births. Achondrogenesis, type 2 is one of several skeletal disorders caused by mutations in the "COL2A1" gene. This gene provides instructions for making a protein that forms type II collagen. This type of collagen is found mostly in cartilage and in the clear gel that fills the eyeball (the vitreous). It is essential for the normal development of bones and other tissues that form the body's supportive framework (connective tissues). Mutations in the "COL2A1" gene interfere with the assembly of type II collagen molecules, which prevents bones and other connective tissues from developing properly.

Achondrogenesis, type 2 is considered an autosomal dominant disorder because one copy of the altered gene in each cell is sufficient to cause the condition. The disorder is not passed on to the next generation, however, because affected individuals hardly survive past puberty.

Collagen improperly formed, enough collagen is made but it is defective.

- Bones fracture easily, sometimes even before birth

- Bone deformity, often severe

- Respiratory problems possible

- Short stature, spinal curvature and sometimes barrel-shaped rib cage

- Triangular face

- Loose joints (double-jointed)

- Poor muscle tone in arms and legs

- Discolouration of the sclera (the 'whites' of the eyes are blue)

- Early loss of hearing possible

Type III is distinguished among the other classifications as being the "progressive deforming" type, wherein a neonate presents with mild symptoms at birth and develops the aforementioned symptoms throughout life. Lifespans may be normal, albeit with severe physical handicapping.

Collagen quantity is sufficient but is not of a high enough quality

- Bones fracture easily, especially before puberty

- Short stature, spinal curvature, and barrel-shaped rib cage

- Bone deformity is mild to moderate

- Early loss of hearing

Similar to Type I, Type IV can be further subclassified into types IVA and IVB characterized by absence (IVA) or presence (IVB) of dentinogenesis imperfecta.

Niemann–Pick type C has a wide clinical spectrum. Affected individuals may have enlargement of the spleen (splenomegaly) and liver (hepatomegaly), or enlarged spleen or liver combined (hepatosplenomegaly), but this finding may be absent in later onset cases. Prolonged jaundice or elevated bilirubin can present at birth. In some cases, however, enlargement of the spleen or liver does not occur for months or years – or not at all. Enlargement of the spleen or liver frequently becomes less apparent with time, in contrast to the progression of other lysosomal storage diseases such as Niemann–Pick disease, Types A and B or Gaucher disease. Organ enlargement does not usually cause major complications.

Progressive neurological disease is the hallmark of Niemann–Pick type C disease, and is responsible for disability and premature death in all cases beyond early childhood. Classically, children with NPC may initially present with delays in reaching normal developmental milestones skills before manifesting cognitive decline (dementia).

Neurological signs and symptoms include cerebellar ataxia (unsteady walking with uncoordinated limb movements), dysarthria (slurred speech), dysphagia (difficulty in swallowing), tremor, epilepsy (both partial and generalized), vertical supranuclear palsy (upgaze palsy, downgaze palsy, saccadic palsy or paralysis), sleep inversion, gelastic cataplexy (sudden loss of muscle tone or drop attacks), dystonia (abnormal movements or postures caused by contraction of agonist and antagonist muscles across joints), most commonly begins with in turning of one foot when walking (action dystonia) and may spread to become generalized, spasticity (velocity dependent increase in muscle tone), hypotonia, ptosis (drooping of the upper eyelid), microcephaly (abnormally small head), psychosis, progressive dementia, progressive hearing loss, bipolar disorder, major and psychotic depression that can include hallucinations, delusions, mutism, or stupor.

In the terminal stages of Niemann–Pick type C disease, the patient is bedridden, with complete ophthalmoplegia, loss of volitional movement and severe dementia.

It has several different types:

- type 1 - Apert syndrome

- type 2 - Crouzon syndrome

- type 3 - Saethre-Chotzen syndrome

- type 5 - Pfeiffer syndrome

A related term, "acrocephalopolysyndactyly" (ACPS), refers to the inclusion of polydactyly to the presentation. It also has multiple types:

- type 1 - Noack syndrome; now classified with Pfeiffer syndrome

- type 2 - Carpenter syndrome

- type 3 - Sakati-Nyhan-Tisdale syndrome

- type 4 - Goodman syndrome; now classified with Carpenter syndrome

- type 5 - Pfeiffer syndrome

It has been suggested that the distinction between "acrocephalosyndactyly" versus "acrocephalopolysyndactyly" should be abandoned.

Mutations in several genes have been associated with the traditional clinical syndromes, termed muscular dystrophy-dystroglycanopathies (MDDG). A new nomenclature based on clinical severity and genetic cause was recently proposed by OMIM. The severity classifications are A (severe), B (intermediate), and C (mild). The subtypes are numbered one to six according to the genetic cause, in the following order: (1) POMT1, (2) POMT2, (3) POMGNT1, (4) FKTN, (5) FKRP, and (6) LARGE.

Most common severe types include:

Acrocephalosyndactylia (or acrocephalosyndactyly) is the common presentation of craniosynostosis and syndactyly.

Kufs disease is one of many diseases categorized under a disorder known as neuronal ceroid lipofuscinosis (NCLs). NCLs are broadly described to create problems with vision, movement and cognitive function. Among all NCLs diseases, Kufs is the only one that does not affect vision, and although this is a distinguishing factor of Kufs, NCLs are typically differentiated by the age at which they appear in a patient

All types of Griscelli syndrome have distinctive skin and hair coloring.

Type 1 is associated with eurological abnormalities. These include delayed development, intellectual disability, seizures, hypotonia and eye abnormalities.

Type 2 - unlike type 1 - is not associated primary neurological disease but is associated with an uncontrolled T lymphocyte expansion and macrophage activation syndrome. It is often associated with the hemophagocytic syndrome. This latter condition may be fatal in the absence of bone marrow transplantation.

Persons with type 3 have the typical light skin and hair coloring but are otherwise normal.

Palmar xanthoma is clinically characterized by yellowish plaques that involve the palms and flexural surfaces of the fingers. Plane xanthomas are characterised by yellowish to orange, flat macules or slightly elevated plaques, often with a central white area which may be localised or generalised. They often arise in the skin folds, especially the palmar creases. They occur in hyperlipoproteinaemia type III and type IIA, and in association with biliary cirrhosis. The presence of palmar xanthomata, like the presence of tendinous xanthomata, is indicative of hypercholesterolaemia.

May–Hegglin anomaly (MHA), also known as Döhle leukocyte inclusions with giant platelets and macrothrombocytopenia with leukocyte inclusions, is a rare genetic disorder of the blood platelets that causes them to be abnormally large.

Tuberoeruptive xanthoma (ILDS E78.210) is clinically characterized by red papules and nodules that appear inflamed and tend to coalesce. Tuberous xanthomata are considered similar, and within the same disease spectrum as eruptive xanthomata.

In the leukocytes, the presence of very small rods (around 3 micrometers), or Döhle-like bodies can be seen in the cytoplasm.

The symptoms of LSD vary, depending on the particular disorder and other variables such as the age of onset, and can be mild to severe. They can include developmental delay, movement disorders, seizures, dementia, deafness, and/or blindness. Some people with LSDhave enlarged livers (hepatomegaly) and enlarged spleens (splenomegaly), pulmonary and cardiac problems, and bones that grow abnormally.