Theoretically, a mutation in any of the may cause disease, but below are some notable ones, with short description of symptoms:

- Adrenoleukodystrophy; leads to progressive brain damage, failure of the adrenal glands and eventually death.

- Alport syndrome; glomerulonephritis, endstage kidney disease, and hearing loss.

- Androgen insensitivity syndrome; variable degrees of undervirilization and/or infertility in XY persons of either gender

- Barth syndrome; metabolism distortion, delayed motor skills, stamina deficiency, hypotonia, chronic fatigue, delayed growth, cardiomyopathy, and compromised immune system.

- Blue cone monochromacy; low vision acuity, color blindness, photophobia, infantile nystagmus.

- Centronuclear myopathy; where cell nuclei are abnormally located in skeletal muscle cells. In CNM the nuclei are located at a position in the center of the cell, instead of their normal location at the periphery.

- Charcot–Marie–Tooth disease (CMTX2-3); disorder of nerves (neuropathy) that is characterized by loss of muscle tissue and touch sensation, predominantly in the feet and legs but also in the hands and arms in the advanced stages of disease.

- Coffin–Lowry syndrome; severe mental retardation sometimes associated with abnormalities of growth, cardiac abnormalities, kyphoscoliosis as well as auditory and visual abnormalities.

- Fabry disease; A lysosomal storage disease causing anhidrosis, fatigue, angiokeratomas, burning extremity pain and ocular involvement.

- Hunter's Syndrome; potentially causing hearing loss, thickening of the heart valves leading to a decline in cardiac function, obstructive airway disease, sleep apnea, and enlargement of the liver and spleen.

- Hypohidrotic ectodermal dysplasia, presenting with hypohidrosis, hypotrichosis, hypodontia

- Kabuki syndrome; multiple congenital anomalies and mental retardation.

- Spinal and bulbar muscular atrophy; muscle cramps and progressive weakness

- Lesch-Nyhan syndrome; neurologic dysfunction, cognitive and behavioral disturbances including self-mutilation, and uric acid overproduction (hyperuricemia)

- Lowe Syndrome; hydrophthalmia, cataracts, intellectual disabilities, aminoaciduria, reduced renal ammonia production and vitamin D-resistant rickets

- Menkes disease; sparse and coarse hair, growth failure, and deterioration of the nervous system

- Nasodigitoacoustic syndrome; mishaped nose, brachydactyly of the distal phalanges, sensorineural deafness

- Nonsyndromic deafness; hearing loss

- Norrie disease; cataracts, leukocoria along with other developmental issues in the eye

- Occipital horn syndrome; deformations in the skeleton

- Ocular albinism; lack of pigmentation in the eye

- Ornithine transcarbamylase deficiency; developmental delay and mental retardation. Progressive liver damage, skin lesions, and brittle hair may also be seen

- Siderius X-linked mental retardation syndrome; cleft lip and palate with mental retardation and facial dysmorphism, caused by mutations in the histone demethylase PHF8

- Simpson-Golabi-Behmel syndrome; coarse faces with protruding jaw and tongue, widened nasal bridge, and upturned nasal tip

- Spinal muscular atrophy caused by UBE1 gene mutation; weakness due to loss of the motor neurons of the spinal cord and brainstem

- Wiskott-Aldrich syndrome; eczema, thrombocytopenia, immune deficiency, and bloody diarrhea

- X-linked Severe Combined Immunodeficiency (SCID); infections, usually causing death in the first years of life

- X-linked sideroblastic anemia; skin paleness, fatigue, dizziness and enlarged spleen and liver.

A genetic disorder is a genetic problem caused by one or more abnormalities in the genome, especially a condition that is present from birth (congenital). Most genetic disorders are quite rare and affect one person in every several thousands or millions.

Genetic disorders may be hereditary, passed down from the parents' genes. In other genetic disorders, defects may be caused by new mutations or changes to the DNA. In such cases, the defect will only be passed down if it occurs in the germ line. The same disease, such as some forms of cancer, may be caused by an inherited genetic condition in some people, by new mutations in other people, and mainly by environmental causes in other people. Whether, when and to what extent a person with the genetic defect or abnormality will actually suffer from the disease is almost always affected by the environmental factors and events in the person's development.

Some types of recessive gene disorders confer an advantage in certain environments when only one copy of the gene is present.

Due to the wide range of genetic disorders that are presently known, diagnosis of a genetic disorder is widely varied and dependent of the disorder. Most genetic disorders are diagnosed at birth or during early childhood, however some, such as Huntington's disease, can escape detection until the patient is well into adulthood.

The basic aspects of a genetic disorder rests on the inheritance of genetic material. With an in depth family history, it is possible to anticipate possible disorders in children which direct medical professionals to specific tests depending on the disorder and allow parents the chance to prepare for potential lifestyle changes, anticipate the possibility of stillbirth, or contemplate termination. Prenatal diagnosis can detect the presence of characteristic abnormalities in fetal development through ultrasound, or detect the presence of characteristic substances via invasive procedures which involve inserting probes or needles into the uterus such as in amniocentesis.

Some specific symptoms vary from one type of leukodystrophy to the next but the vast majority of symptoms are shared as the causes for the disease generally have the same effects. Symptoms are dependent on the age of onset, which is predominantly in infancy and early childhood, although the exact time of onset may be difficult to determine. Hyperirritability and hypersensitivity to the environment are common, as well as some tell-tale physical signs including muscle rigidity and a backwards-bent head. Botox therapy is often used to treat patients with spasticity. Juvenile and adult onsets display similar symptoms including a decrease or loss in hearing and vision. While children do experience optic and auditory degeneration, the course of the disease is usually too rapid, causing death relatively quickly, whereas adults may live with these conditions for many years. In children, spastic activity often precedes progressive ataxia and rapid cognitive deterioration which has been described as mental retardation. Epilepsy is commonplace for patients of all ages. More progressed patients show weakness in deglutition, leading to spastic coughing fits due to inhaled saliva. Classic symptomatic progression of juvenile x-linked adrenoleukodystrophy is shown in the 1992 film, "Lorenzo's Oil".

Course and timetable are dependent on the age of onset with infants showing a lifespan of 2–8 years, juveniles 2–10 years and adults typically 10+ years. Adults typically see an extended period of stability followed by a decline to a vegetative state and death. While treatments do exist, most are in the experimental phase and can only promise a halt in the progression of symptoms, although some gene therapies have shown some symptomatic improvement. The debilitating course of the disease has led to numerous philosophical and ethical arguments over experimental clinical trials, patients’ rights and physician-assisted suicide.

Chondrodysplasia punctata is a clinically and genetically diverse group of rare diseases, first described by Erich Conradi (1882–1968), that share the features of stippled epiphyses and skeletal changes.

Types include:

- Rhizomelic chondrodysplasia punctata , ,

- X-linked recessive chondrodysplasia punctata

- Conradi-Hünermann syndrome

- Autosomal dominant chondrodysplasia punctata

The signs and symptoms of X-linked recessive hypoparathyroidism are characteristic of hypoparathyroidism and its consequent hypocalcemia. They include acute symptoms, like paresthesia, twitching of the hands and feet, unconsciousness, and trouble breathing; and chronic symptoms, including seizures, tiredness, irritability, cardiac insufficiency, abnormal heart rhythms, papilledema, cataracts, calcium deposits in the brain, and loss or brittleness of hair, skin, and nails.

The most common X-linked recessive disorders are:

- Red-green color blindness, a very common trait in humans and frequently used to explain X-linked disorders. Between seven and ten percent of men and 0.49% to 1% of women are affected. Its commonness may be explained by its relatively benign nature. It is also known as daltonism.

- Hemophilia A, a blood clotting disorder caused by a mutation of the Factor VIII gene and leading to a deficiency of Factor VIII. It was once thought to be the "royal disease" found in the descendants of Queen Victoria. This is now known to have been Hemophilia B (see below).

- Hemophilia B, also known as Christmas Disease, a blood clotting disorder caused by a mutation of the Factor IX gene and leading to a deficiency of Factor IX. It is rarer than hemophilia A. As noted above, it was common among the descendants of Queen Victoria.

- Duchenne muscular dystrophy, which is associated with mutations in the dystrophin gene. It is characterized by rapid progression of muscle degeneration, eventually leading to loss of skeletal muscle control, respiratory failure, and death.

- Becker's muscular dystrophy, a milder form of Duchenne, which causes slowly progressive muscle weakness of the legs and pelvis.

- X-linked ichthyosis, a form of ichthyosis caused by a hereditary deficiency of the steroid sulfatase (STS) enzyme. It is fairly rare, affecting one in 2,000 to one in 6,000 males.

- X-linked agammaglobulinemia (XLA), which affects the body's ability to fight infection. XLA patients do not generate mature B cells. B cells are part of the immune system and normally manufacture antibodies (also called immunoglobulins) which defends the body from infections (the humoral response). Patients with untreated XLA are prone to develop serious and even fatal infections.

- Glucose-6-phosphate dehydrogenase deficiency, which causes nonimmune hemolytic anemia in response to a number of causes, most commonly infection or exposure to certain medications, chemicals, or foods. Commonly known as "favism", as it can be triggered by chemicals existing naturally in broad (or fava) beans.

X-linked myotubular myopathy (MTM) is a form of centronuclear myopathy (CNM) associated with myotubularin 1.

Genetically inherited traits and conditions are often referred to based upon whether they are located on the "sex chromosomes" (the X or Y chromosomes) versus whether they are located on "autosomal" chromosomes (chromosomes other than the X or Y). Thus, genetically inherited conditions are categorized as being sex-linked (e.g., X-linked) or autosomal. Females have two X-chromosomes, while males only have a single X chromosome, and a genetic abnormality located on the X chromosome is much more likely to cause clinical disease in a male (who lacks the possibility of having the normal gene present on any other chromosome) than in a female (who is able to compensate for the one abnormal X chromosome).

The X-linked form of MTM is the most commonly diagnosed type. Almost all cases of X-linked MTM occurs in males. Females can be "carriers" for an X-linked genetic abnormality, but usually they will not be clinically affected themselves. Two exceptions for a female with a X-linked recessive abnormality to have clinical symptoms: one is a manifesting carrier and the other is X-inactivation. A manifesting carrier usually has no noticeable problems at birth; symptoms show up later in life. In X-inactivation, the female (who would otherwise be a carrier, without any symptoms), actually presents with full-blown X-linked MTM. Thus, she congenitally presents (is born with) MTM.

Thus, although" MTM1" mutations most commonly cause problems in boys, these mutations can also cause clinical myopathy in girls, for the reasons noted above. Girls with myopathy and a muscle biopsy showing a centronuclear pattern should be tested for "MTM1" mutations.

Many clinicians and researchers use the abbreviations XL-MTM, XLMTM or X-MTM to emphasize that the genetic abnormality for myotubular myopathy (MTM) is X-linked (XL), having been identified as occurring on the X chromosome. The specific gene on the X chromosome is referred to as MTM-1. In theory, some cases of CNM may be caused by an abnormality on the X chromosome, but located at a different site from the gene "MTM1", but currently "MTM1" is the only X-linked genetic mutation site identified for myotubular or centronuclear myopathy. Clinical suspicion for X-linked inheritance would be a disease affecting multiple boys (but no girls) and a pedigree chart showing inheritance only through the maternal (mother’s) side of each generation.

Leukodystrophy is one of a group of disorders characterized by degeneration of the white matter in the brain. The word "leukodystrophy" comes from the Greek roots "leuko", "white", "dys", "abnormal", and "troph", "growth". The leukodystrophies are caused by imperfect growth or development of the myelin sheath, the fatty covering that acts as an insulator around nerve fibers.

When damage occurs to white matter, immune responses can lead to inflammation in the CNS, along with loss of myelin. The degeneration of white matter can be seen in a MRI and used to diagnose leukodystrophy. Leukodystrophy is characterized by specific symptoms including decreased motor function, muscle rigidity, and eventually degeneration of sight and hearing. While the disease is fatal, the age of onset is a key factor as infants are given a lifespan of 2–8 years (sometimes longer), while adults typically live more than a decade after onset. There is a great lack of treatment, although cord blood and hematopoietic stem cell transplantation (bone marrow transplant) seem to help in certain types while further research is being done.

The combined incidence of the leukodystrophies is estimated at 1:7,600. The majority of types involve the inheritance of a recessive, dominant, or X-linked trait, while others, although involving a defective gene, are the result of spontaneous mutation rather than genetic inheritance.

Hypohidrotic ectodermal dysplasia (also known as "anhidrotic ectodermal dysplasia", and "Christ-Siemens-Touraine syndrome") is one of about 150 types of ectodermal dysplasia in humans. Before birth, these disorders result in the abnormal development of structures including the skin, hair, nails, teeth, and sweat glands.

Most children with Allan–Herndon–Dudley syndrome have weak muscle tone (hypotonia) and underdevelopment of many muscles (muscle hypoplasia). As they get older, they usually develop joint deformities called contractures, which restrict the movement of certain joints. Abnormal muscle stiffness (spasticity), muscle weakness, and involuntary movements of the arms and legs also limit mobility. As a result, many people with Allan–Herndon–Dudley syndrome are unable to walk independently and become wheelchair-bound by adulthood.

Most people with hypohidrotic ectodermal dysplasia have a reduced ability to sweat (hypohidrosis) because they have fewer sweat glands than normal or their sweat glands do not function properly. Sweating is a major way that the body controls its temperature; as sweat evaporates from the skin, it cools the body. An inability to sweat can lead to a dangerously high body temperature (hyperthermia) particularly in hot weather. In some cases, hyperthermia can cause life-threatening medical problems.

Affected individuals tend to have sparse scalp and body hair (hypotrichosis). The hair is often light-coloured, brittle, and slow-growing. This condition is also characterized by absent teeth (hypodontia) or teeth that are malformed. The teeth that are present are frequently small and pointed.

Hypohidrotic ectodermal dysplasia is associated with distinctive facial features including a prominent forehead, thick lips, and a flattened bridge of the nose. Additional features of this condition include thin, wrinkled, and dark-colored skin around the eyes; chronic skin problems such as eczema; and a bad-smelling discharge from the nose (ozena).

Hypohidrotic ectodermal dysplasia is the most common form of ectodermal dysplasia in humans. It is estimated to affect at least 1 in 17,000 people worldwide.

Gordon syndrome is an extremely rare disorder that belongs to a group of genetic disorders known as the distal arthrogryposes. These disorders typically involve stiffness and impaired mobility of certain joints of the lower arms and legs (distal extremities) including the knees, elbows, wrists, and/or ankles. These joints tend to be permanently fixed in a bent or flexed position (contractures). Gordon syndrome is characterized by the permanent fixation of several fingers in a flexed position (camptodactyly), abnormal bending inward of the foot (clubfoot or talipes), and, less frequently, incomplete closure of the roof of the mouth (cleft palate). In some cases, additional abnormalities may also be present. The range and severity of symptoms may vary from case to case. Gordon syndrome is inherited as an autosomal dominant trait.

X-linked recessive hypoparathyroidism is a rare, congenital form of hypoparathyroidism.

Gordon syndrome (GS), or distal arthrogryposis type 3, is a rare, autosomal dominant disorder characterized by cleft palate and congenital contractures of the hands and feet.

Clinically, three distinct patterns of palmoplantar keratoderma may be identified: diffuse, focal, and punctate.

The skin lesions evolve through characteristic stages:

1. blistering (from birth to about four months of age),

2. a wart-like rash (for several months),

3. swirling macular hyperpigmentation (from about six months of age into adulthood), followed by

4. linear hypopigmentation.

Alopecia, hypodontia, abnormal tooth shape, and dystrophic nails are observed. Some patients have retinal vascular abnormalities predisposing to retinal detachment in early childhood. Cognitive delays/mental retardation are occasionally seen.

Discolored skin is caused by excessive deposits of melanin (normal skin pigment).

Most newborns with IP will develop discolored skin within the first two weeks.

The pigmentation involves the trunk and extremities, is slate-grey, blue or brown, and is distributed in irregular marbled or wavy lines.

The discoloration sometimes fades with age.

Neurological problems can include: cerebral atrophy, the formation of small cavities in the central white matter of the brain, and the loss of neurons in the cerebellar cortex.

About 20% of children with IP will have slow motor development, muscle weakness in one or both sides of the body, mental retardation, and seizures.

They are also likely to have visual problems, which can include: crossed eyes, cataracts, and severe visual loss.

Dental problems are common, and include missing or peg-shaped teeth - patients with IP often keep milk teeth into adult life.

Breast anomalies can occur in 1% of patients; anomalies can include hypoplasia and supernumerary nipples.

Skeletal and structural anomalies can occur in approximately 14% of patients, including:

- Somatic asymmetry,

- Hemivertebrae,

- Scoliosis,

- Spina bifida,

- Syndactyly,

- Acheiria (congenital absence of the hands - note: other limbs may be affected),

- Ear anomalies,

- Extra ribs,

- Skull deformities,

- Primary pulmonary hypertension,

- Cardiopulmonary failure

X-linked spinal muscular atrophy type 2 (SMAX2, XLSMA), also known as arthrogryposis multiplex congenita X-linked type 1 (AMCX1), is a rare neurological disorder involving death of motor neurons in the anterior horn of spinal cord resulting in generalised muscle wasting (atrophy). The disease is caused by a mutation in "UBA1" gene and is passed in a X-linked recessive manner by carrier mothers to affected sons.

Affected babies have general muscle weakness, weak cry and floppy limbs; consequently, the condition is usually apparent at or even before birth. Symptoms resemble the more severe forms of the more common spinal muscular atrophy (SMA); however, SMAX2 is caused by a different genetic defect and only genetic testing can correctly identify the disease.

The disorder is usually fatal in infancy or early childhood due to progressive respiratory failure, although survival into teenage years have been reported. As with many genetic disorders, there is no known cure to SMAX2. Appropriate palliative care may be able to increase quality of life and extend lifespan.

Melnick–Needles syndrome (MNS), also known as Melnick–Needles osteodysplasty, is an extremely rare congenital disorder that affects primarily bone development. Patients with Melnick–Needles syndrome have typical faces (exophthalmos, full cheeks, micrognathia and malalignment of teeth), flaring of the metaphyses of long bones, s-like curvature of bones of legs, irregular constrictions in the ribs, and sclerosis of base of skull.

In males, the disorder is nearly always lethal in infancy. Lifespan of female patients might not be affected.

Melnick–Needles syndrome is associated with mutations in the "FLNA" gene and is inherited in an X-linked dominant manner. As with many genetic disorders, there is no known cure to MNS.

The disorder was first described by John C. Melnick and Carl F. Needles in 1966 in two multi-generational families.

Conradi–Hünermann syndrome is a form of chondrodysplasia punctata, a group of rare genetic disorders of skeletal development involving abnormal accumulations of calcium salts within the growing ends of long bones. Conradi–Hünermann syndrome is commonly associated with mild to moderate growth deficiency, disproportionate shortening of long bones, particularly those of the upper arms and the thigh bones, short stature, and/or curvature of the spine. In rare cases, intellectual disability may also be present. While evidence suggests that Conradi–Hünermann syndrome predominantly occurs in females and is usually inherited as an X-linked dominant trait, rare cases in which males were affected have also been reported.

The genetics of Conradi–Hünermann syndrome has perplexed medical geneticists, pediatricians and dermatologists for some time, but a number of perplexing features of the genetics of the syndrome have now been resolved, including the fact that the disease is caused by mutations in a gene, and these mutations are simple substitutions, deletions or insertions and are therefore not "unstable". Scientists are still trying to understand exactly where the mutation occurs so that they can correct it.

Allan–Herndon–Dudley syndrome is a rare X-linked inherited disorder of brain development that causes moderate to severe intellectual disability and problems with movement. This condition, which occurs almost exclusively in males, disrupts development from before birth.

Allan–Herndon–Dudley syndrome, which is named eponymously for William Allan, Florence C. Dudley, and C. Nash Herndon, results from a mutation of the thyroid hormone transporter MCT8 (also referred to as SLC16A2). Consecutively, thyroid hormones are unable to enter the nervous system, which depends on thyroid signaling for proper function and development.

Prenatal and neonatal diagnosis of boomerang dysplasia includes several prominent features found in other osteochondrodysplasias, though the "boomerang" malformation seen in the long bones is the delineating factor.

Featured symptoms of boomerang dysplasia include: dwarfism (a lethal type of infantile dwarfism caused by systemic bone deformities), underossification (lack of bone formation) in the limbs, spine and ilium (pelvis); proliferation of multinucleated giant-cell chondrocytes (cells that produce cartilage and play a role in skeletal development - chondrocytes of this type are rarely found in osteochondrodysplasias), brachydactyly (shortened fingers) and (undersized, shortened bones).

The characteristic "boomerang" malformation presents intermittently among random absences of long bones throughout the skeleton, in affected individuals. For example, one individual may have an absent radius and fibula, with the "boomerang" formation found in both ulnas and tibias. Another patient may present "boomerang" femora, and an absent tibia.

Diffuse palmoplantar keratoderma is a type of palmoplantar keratoderma that is characterized by an even, thick, symmetric hyperkeratosis over the whole of the palm and sole, usually evident at birth or in the first few months of life. Restated, diffuse palmoplantar keratoderma is an autosomal dominant disorder in which hyperkeratosis is confined to the palms and soles. The two major types can have a similar clinical appearance:

- "Diffuse epidermolytic palmoplantar keratoderma" (also known as "Palmoplantar keratoderma cum degeneratione granulosa Vörner," "Vörner's epidermolytic palmoplantar keratoderma", and "Vörner keratoderma") is one of the most common patterns of palmoplantar keratoderma, an autosomal dominant condition that presents within the first few months of life, characterized by a well-demarcated, symmetric thickening of palms and soles, often with a "dirty" snakeskin appearance due to underlying epidermolysis.

- "Diffuse nonepidermolytic palmoplantar keratoderma" (also known as "Diffuse orthohyperkeratotic keratoderma," "Hereditary palmoplantar keratoderma," "Keratosis extremitatum progrediens," "Keratosis palmoplantaris diffusa circumscripta," "Tylosis," "Unna–Thost disease", and "Unna–Thost keratoderma") is inherited as an autosomal dominant condition and is present from infancy, characterized by a well-demarcated, symmetric, often "waxy" keratoderma involving the whole of the palms and soles.

Centronuclear myopathies (CNM) are a group of congenital myopathies where cell nuclei are abnormally located in skeletal muscle cells. In CNM the nuclei are located at a position in the center of the cell, instead of their normal location at the periphery.

Symptoms of CNM include severe hypotonia, hypoxia-requiring breathing assistance, and scaphocephaly. Among centronuclear myopathies, the X-linked myotubular myopathy form typically presents at birth, and is thus considered a congenital myopathy. However, some centronuclear myopathies may present later in life.

Incontinentia pigmenti (IP) is a rare genetic disorder that affects the skin, hair, teeth, nails, and central nervous system. It is named from its appearance under a microscope. It is also known as Bloch–Siemens syndrome, Bloch–Sulzberger disease, Bloch–Sulzberger syndrome, melanoblastosis cutis, and nevus pigmentosus systematicus.

It is characterized by skin abnormalities that begin in childhood, usually a blistering rash which heals, followed by the development of harder skin growths. The skin may develop grey or brown patches which fade with time. Other symptoms can include hair loss, dental abnormalities, eye abnormalities that can lead to vision loss, and lined or pitted fingernails and toenails. Associated problems can include delayed development, intellectual disability, seizures, and other neurological problems. There is no specific treatment, individual conditions must be managed by specialists.