The symptoms of Freeman–Sheldon syndrome include drooping of the upper eyelids, strabismus, low-set ears, a long philtrum, gradual hearing loss, scoliosis, and walking difficulties. Gastroesophageal reflux has been noted during infancy, but usually improves with age. The tongue may be small, and the limited movement of the soft palate may cause nasal speech. Often there is an H- or Y-shaped dimpling of the skin over the chin.

Individuals affected by AAA have adrenal insufficiency/Addison's disease due to ACTH resistance, alacrima (absence of tear secretion), and achalasia (a failure of a ring of muscle fibers, such as a sphincter, to relax) of the lower esophageal sphincter at the cardia which delays food going to the stomach and causes dilation of the thoracic esophagus. There may also be signs of autonomic dysfunction with AAA, such as pupillary abnormalities, an abnormal reaction to intradermal histamine, abnormal sweating, orthostatic hypotension, and disturbances of the heart rate. Hypoglycemia (low blood sugar) is often mentioned as an early sign. The disorder has also been associated with mild mental retardation.

The syndrome is highly variable. Managed effectively, affected individuals can have a normal lifespan and bear children.

Symptoms(and signs) that are consistent with this disorder are the following:

Freeman–Sheldon syndrome (FSS), also termed distal arthrogryposis type 2A (DA2A), craniocarpotarsal dysplasia (or dystrophy), Cranio-carpo-tarsal syndrome, Windmill-Vane-Hand syndrome, or Whistling-face syndrome, was originally described by Freeman and Sheldon in 1938. Freeman–Sheldon syndrome is a rare form of multiple congenital contracture (MCC) syndromes (arthrogryposes) and is the most severe form of distal arthrogryposis (DA).

Patients with Sack–Barabas syndrome have thin, fragile skin, especially in the chest and abdomen, that bruises easily; hands and feet may have an aged appearance. Skin is soft but not overly stretchy.

Facial features are often distinctive, including protruding eyes, a thin nose and lips, sunken cheeks, and a small chin.

Other signs of the disorder include hypermobility of joints, tearing of tendons and muscles, painfully swollen veins in the legs, lung collapse, and slow wound healing following injury or surgery.

Infants with the condition may be born with hip dislocations and clubfeet.

Unpredictable ruptures of arteries and organs are serious complications of SBS. Ruptured arteries can cause internal bleeding, stroke, or shock, the most common cause of death in patients with this disorder.

Rupture of the intestine is seen in 25 to 30 percent of affected individuals and tearing of the uterus during pregnancy affects 2 to 3 percent of women. Although these symptoms are rare in childhood, more than 80 percent of patients experience severe complications by the age of 40. Teenage boys are at high risk for arterial rupture, often being fatal.

Triple-A syndrome or AAA syndrome, also known as achalasia-addisonianism-alacrima syndrome or Allgrove syndrome, is a rare autosomal recessive congenital disorder. In most cases, there is no family history of it. The syndrome was first identified by Jeremy Allgrove and colleagues in 1978. The syndrome involves achalasia, addisonianism (adrenal insufficiency of primary type), and alacrima (insufficiency of tears). Alacrima is usually the earliest manifestation. It is a progressive disorder that can take years to develop the full blown clinical picture.

Autoimmune polyendocrine syndrome type 2, a form of autoimmune polyendocrine syndrome also known as Schmidt's syndrome, or APS-II, is the most common form of the polyglandular failure syndromes. It is heterogeneous and has not been linked to one gene. Rather, individuals are at a higher risk when they carry a particular human leukocyte antigen (HLA-DQ2, HLA-DQ8 and HLA-DR4). APS-II affects women to a greater degree than men.

There is no specific treatment or cure for individuals affected with this type of syndrome, though some of the abnormal physical features may be surgically correctable.

The fifth type of hyper-IgM syndrome has been characterized in three patients from France and Japan. The symptoms are similar to hyper IgM syndrome type 2, but the AICDA gene is intact. These three patients instead had mutations in the catalytic domain of uracil-DNA glycosylase, an enzyme that removes uracil from DNA. In both type 2 and type 5 hyper-IgM syndromes, the patients are profoundly deficient in IgG and IgA because the B cells can't carry out the recombination steps necessary to class-switch.

There is a range of signs and symptoms including cleft lip or palate, mental retardation and various forms of ectodermal dysplasia. Additional symptoms may include fused eyelids, absent nails, delayed bone growth and dry skin. It is believed that this syndrome follows an autosomal dominant pattern of inheritance with incomplete penetrance, and caused by a mutation affecting the TP63 gene. It has been suggested that this syndrome, AEC syndrome and Rapp–Hodgkin syndrome may be variations of the same disease.

It causes facial abnormalities, skeletal malformation and occasionally neural tube defects; the skeletal disfigurements resolve to a degree in the course of development.

Mutations in different parts of the gene may lead to deafness or Stickler syndrome type III (eye problems: myopia, retinal detachment and skeletal abnormalities).

Infants and children: Infants that are born with Weissenbacher-Zweymüller syndrome usually have short bones in their arms and legs. The thigh and upper arm bones are wider than usual resulting in a dumbbell-shape while the bones of the vertebrae may be abnormal. Typical abnormal facial features can be wide-set protruding eyes (hypertelorism), a small and upturned nose with a flat bridge, small jaw (micrognathia) and a cleft palate. Some infants have high-frequency hearing loss. Infants may also exhibit a psychomotor delay. After the period of growth deficiency the individual makes improvements in bone growth leading to a normal physical development around age 5 or 6.

Adults: Many with Weissenbacher-Zweymüller syndrome have a catch-up growth phase causing the adults to not be unusually short. Many adults still will have hearing loss and typical abnormal facial features of Weissenbacher-Zweymüller syndrome.

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.

The three most common symptoms of Opitz G/BBB syndrome (both type I & II) are hypertelorism (exceptionally wide-spaced eyes), laryngo-tracheo-esophalgeal defects (including clefts and holes in the palate, larynx, trachea and esophagus) and hypospadias (urinary openings in males not at the tip of the penis) (Meroni, Opitz G/BBB syndrome, 2012). Abnormalities in the larynx, trachea and esophagus can cause significant difficulty breathing and/or swallowing and can result in reoccurring pneumonia and life-threatening situations. Commonly, there may be a gap between the trachea and esophagus, referred to as a laryngeal cleft; which can allow food or fluid to enter the airway and make breathing and eating a difficult task.

Genital abnormalities like a urinary opening under the penis (hypospadias), undescended testes (cryptorchidism), underdeveloped scrotum and a scrotum divided into two lobes (bifid scrotum) can all be commonplace for males with the disease.

Developmental delays of the brain and nervous system are also common in both types I and II of the disease. 50% of people with Opitz G/BBB Syndrome will experience developmental delay and mild intellectual disability. This can impact motor skills, speech and learning capabilities. Some of these instances are likened to autistic spectrum disorders. Close to half of the people with Opitz G/BBB Syndrome also have a cleft lip (hole in the lip opening) and possibly a cleft palate (hole in the roof of the mouth), as well. Less than half of the people diagnosed have heart defects, imperforate anus (obstructed anal opening), and brain defects. Of all the impairments, female carriers of X-linked Type I Opitz G/BBB Syndrome usually only have ocular hypertelorism.

Symptoms vary from one type of the syndrome to another and from one patient to another, but they include:

- Very pale or brilliantly blue eyes, eyes of two different colors (complete heterochromia), or eyes with one iris having two different colors (sectoral heterochromia)

- A forelock of white hair ("poliosis"), or premature graying of the hair

- Appearance of wide-set eyes due to a prominent, broad nasal root ("dystopia canthorum")—particularly associated with Type I) also known as "telecanthus"

- Moderate to profound hearing loss (higher frequency associated with Type II);

- A low hairline and eyebrows that meet in the middle ("synophrys")

- Patches of white skin pigmentation, in some cases

- Abnormalities of the arms, associated with Type III

- neurologic manifestations, associated with Type IV

- Cleft lip, mostly associated with Type I

Waardenburg syndrome has also been associated with a variety of other congenital disorders, such as intestinal and spinal defects, elevation of the scapula and cleft lip and palate. Sometimes this is concurrent with Hirschsprung disease.

Sack–Barabas syndrome is an older name for the medical condition Ehlers-Danlos syndrome, vascular type. It affects the body's blood vessels and organs, making them prone to rupture.

X-linked type I Opitz G/BBB Syndrome is diagnosed on clinical findings, but those findings can vary greatly: even within the same family. Manifestations of X-linked type I are classified in the frequent/major findings and minor findings that are found in less than 50% of individuals.

The three major findings that suggest a person has X-linked Type I Opitz G/BBB Syndrome:

1. Ocular hypertelorism (~100% cases)

2. Hypospadias (85-90% cases)

3. Laryngotracheoesophageal abnormalities (60-70%)

Minor findings found in less than 50% of individuals:

1. Developmental delay (especially intellectually)

2. Cleft lip/palate

3. Congenital heart defects

4. Imperforate (blocked) anus

5. Brain defects (especially corpus callosum)

In 1989, Hogdall used ultrasonographs to diagnose X-linked Type I Opitz G/BBB Syndrome after 19 weeks of pregnancy, by identifying hypertelorism (widely-spaced eyes) and hypospadias (irregular urinary tract openings in the penis).

There is also molecular genetic testing available to identify mutations leading to Opitz G/BBB Syndrome. X-linked Type I testing must be done on MID1, since this is the only gene that is known to cause Type I Opitz G/BBB Syndrome. Two different tests can be performed: sequence analysis and deletion/duplication analysis. In the sequence analysis a positive result would detect 15-50% of the DNA sequence mutated, while a deletion/duplication positive result would find deletion or duplication of one or more exons of the entire MID1 gene.

The differential diagnosis is quite extensive and includes

- Buschke–Fischer–Brauer disease

- Curth–Macklin ichthyosis

- Gamborg Nielsen syndrome

- Greither disease

- Haber syndrome

- Hereditary punctate palmoplantar keratoderma

- Jadassohn–Lewandowsky syndrome

- Keratosis follicularis spinulosa decalvans

- Keratosis linearis with ichthyosis congenital and sclerosing keratoderma syndrome

- Meleda disease

- Mucosa hyperkeratosis syndrome

- Naegeli–Franceschetti–Jadassohn syndrome

- Naxos disease

- Olmsted syndrome

- Palmoplantar keratoderma and leukokeratosis anogenitalis

- Pandysautonomia

- Papillomatosis of Gougerot and Carteaud

- Papillon–Lefèvre syndrome

- Punctate porokeratotic keratoderma

- Richner–Hanhart syndrome

- Schöpf–Schulz–Passarge syndrome

- Unna Thost disease

- Vohwinkel syndrome

- Wong's dermatomyositis

As of 2017 there are 13 types of Ehlers-Danlos syndromes, with a significant overlap in features.

Hypermobile EDS - characterized primarily by joint hypermobility affecting both large and small joints, which may lead to recurrent joint dislocations and subluxations (partial dislocation). In general, people with this type have soft, smooth and velvety skin with easy bruising and chronic pain of the muscles and/or bones.

Classical EDS - associated with extremely elastic (stretchy), smooth skin that is fragile and bruises easily; wide, atrophic scars (flat or depressed scars); and joint hypermobility. Molluscoid pseudotumors (calcified hematomas over pressure points such as the elbow) and spheroids (fat-containing cysts on forearms and shins) are also frequently seen. Hypotonia and delayed motor development may occur.

Vascular EDS - characterized by thin, translucent skin that is extremely fragile and bruises easily. Arteries and certain organs such as the intestines and uterus are also fragile and prone to rupture. People with this type typically have short stature; thin scalp hair; and characteristic facial features including large eyes, a thin nose, and lobeless ears. Joint hypermobility is present, but generally confined to the small joints (fingers, toes). Other common features include club foot; tendon and/or muscle rupture; acrogeria (premature aging of the skin of the hands and feet); early onset varicose veins; pneumothorax (collapse of a lung); recession of the gums; and a decreased amount of fat under the skin.

Kyphoscoliosis EDS - associated with severe hypotonia at birth, delayed motor development, progressive scoliosis (present from birth), and scleral fragility. Affected people may also have easy bruising; fragile arteries that are prone to rupture; unusually small corneas; and osteopenia (low bone density). Other common features include a "marfanoid habitus" which is characterized by long, slender fingers (arachnodactyly); unusually long limbs; and a sunken chest (pectus excavatum) or protruding chest (pectus carinatum).

Arthrochalasia EDS - characterized by severe joint hypermobility and congenital hip dislocation. Other common features include fragile, elastic skin with easy bruising; hypotonia; kyphoscoliosis (kyphosis and scoliosis); and mild osteopenia.

Dermatosparaxis EDS - associated with extremely fragile skin leading to severe bruising and scarring; saggy, redundant skin, especially on the face; and hernias.

Brittle Cornea Syndrome (BCS) characterized by thin cornea, early onset progressive keratoglobus; and blue sclerae.

Classical-like EDS (clEDS) characterized by skin hyperextensibility with velvety skin texture and absence of atrophic scarring, generalized joint hypermobility (GJH) with or without recurrent dislocations (most often shoulder and ankle), and easily bruised skin or spontaneous ecchymoses (discolorations of the skin resulting from bleeding underneath).

Spondylodysplastic EDS (spEDS) characterized by short stature (progressive in childhood), muscle hypotonia (ranging from severe congenital, to mild later-onset), and bowing of limbs.

Musculocontractural EDS (mcEDS) characterized by congenital multiple contractures, characteristically adduction-flexion contractures and/or talipes equinovarus (clubfoot), characteristic craniofacial features, which are evident at birth or in early infancy, and skin features such as skin hyperextensibility, easy bruisability, skin fragility with atrophic scars, increased palmar wrinkling.

Myopathic EDS (mEDS) characterized by congenital muscle hypotonia, and/or muscle atrophy, that improves with age, Proximal joint contractures (joints of the knee, hip and elbow); and hypermobility of distal joints (joints of the ankles, wrists, feet and hands).

Periodontal EDS (pEDS) characterized by severe and intractable periodontitis of early onset (childhood or adolescence), lack of attached gingiva, pretibial plaques; and family history of a first-degree relative who meets clinical criteria.

Cardiac-valvular EDS (cvEDS) characterized by severe progressive cardiac-valvular problems (aortic valve, mitral valve), skin problems (hyperextensibility, atrophic scars, thin skin, easy bruising) and joint hypermobility (generalized or restricted to small joints).

There are several disorders that share some characteristics with Ehlers–Danlos syndrome. For example, in cutis laxa the skin is loose, hanging, and wrinkled. In EDS, the skin can be pulled away from the body but is elastic and returns to normal when let go. In Marfan syndrome, the joints are very mobile and similar cardiovascular complications occur. People with EDS tend to have a "Marfanoid" appearance (e.g., tall, skinny, long arms and legs, "spidery" fingers). However, physical appearance and features in several types of Ehlers–Danlos syndrome also have characteristics including short stature, large eyes, and the appearance of a small mouth and chin, due to a small palate. The palate can have a high arch, causing dental crowding. Blood vessels can sometimes be easily seen through translucent skin, especially on the chest. The genetic connective tissue disorder, Loeys-Dietz Syndrome, also has symptoms that overlap with EDS.

In the past, Menkes disease, a copper metabolism disorder, was thought to be a form of Ehlers–Danlos syndrome. It is not uncommon for patients to be misdiagnosed with fibromyalgia, bleeding disorders or other disorders that can mimic EDS symptoms before a correct diagnosis is made. Because of these similar disorders and complications that can arise from an un-monitored case of EDS, a correct diagnosis is very important. Pseudoxanthoma elasticum (PXE) is worth consideration in diagnosing a patient.

Griscelli syndrome type 2 (also known as "partial albinism with immunodeficiency") is a rare autosomal recessive syndrome characterized by variable pigmentary dilution, hair with silvery metallic sheen, frequent pyogenic infections, neutropenia, and thrombocytopenia.

Individuals with Stickler syndrome experience a range of signs and symptoms. Some people have no signs and symptoms; others have some or all of the features described below. In addition, each feature of this syndrome may vary from subtle to severe.

A characteristic feature of Stickler syndrome is a somewhat flattened facial appearance. This is caused by underdeveloped bones in the middle of the face, including the cheekbones and the bridge of the nose. A particular group of physical features, called the Pierre Robin sequence, is common in children with Stickler syndrome. Robin sequence includes a U-shaped or sometimes V-shaped cleft palate (an opening in the roof of the mouth) with a tongue that is too large for the space formed by the small lower jaw. Children with a cleft palate are also prone to ear infections and occasionally swallowing difficulties.

Many people with Stickler syndrome are very nearsighted (described as having high myopia) because of the shape of the eye. People with eye involvement are prone to increased pressure within the eye (ocular hypertension) which could lead to glaucoma and tearing or detachment of the light-sensitive retina of the eye (retinal detachment). Cataract may also present as an ocular complication associated with Stickler's Syndrome. The jelly-like substance within the eye (the vitreous humour) has a distinctive appearance in the types of Stickler syndrome associated with the COL2A1 and COL11A1 genes. As a result, regular appointments to a specialist ophthalmologist are advised. The type of Stickler syndrome associated with the COL11A2 gene does not affect the eye.

People with this syndrome have problems that affect things other than the eyes and ears. Arthritis, abnormality to ends of long bones, vertebrae abnormality, curvature of the spine, scoliosis, joint pain, and double jointedness are all problems that can occur in the bones and joints. Physical characteristics of people with Stickler can include flat cheeks, flat nasal bridge, small upper jaw, pronounced upper lip groove, small lower jaw, and palate abnormalities, these tend to lessen with age and normal growth and palate abnormalities can be treated with routine surgery.

Another sign of Stickler syndrome is mild to severe hearing loss that, for some people, may be progressive (see hearing loss with craniofacial syndromes). The joints of affected children and young adults may be very flexible (hypermobile). Arthritis often appears at an early age and worsens as a person gets older. Learning difficulties, not intelligence, can also occur because of hearing and sight impairments if the school is not informed and the student is not assisted within the learning environment.

Stickler syndrome is thought to be associated with an increased incidence of mitral valve prolapse of the heart, although no definitive research supports this.

Carpenter syndrome presents several features:

- Tower-shaped skull (craniosynostosis)

- Additional or fused digits (fingers and toes)

- Obesity

- Reduced height

Intellectual disability is also common with the disorder, although some patients may have average intellectual capacity.

The RASopathies are developmental syndromes caused by germline mutations (or in rare cases by somatic mosaicism) in genes that alter the Ras subfamily and mitogen-activated protein kinases that control signal transduction, including:

- Capillary malformation-AV malformation syndrome

- Autoimmune lymphoproliferative syndrome

- Cardiofaciocutaneous syndrome

- Hereditary gingival fibromatosis type 1

- Neurofibromatosis type 1

- Noonan syndrome

- Costello syndrome, Noonan-like

- Legius syndrome, Noonan-like

- Noonan syndrome with multiple lentigines, formerly called LEOPARD syndrome, Noonan-like

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

- Hypoparathyroidism

- Hypogonadism

- Vitiligo

- Alopecia

- Malabsorption

- Anemia

- Cataract

- Adrenal hyperplasia

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.