Patients with CHH usually suffer from cellular immunodeficiency. In the study of 108 Finnish patients with CHH there was detected mild to moderate form of lymphopenia, decreased delayed type of hypersensitivity and impaired responses to phytohaemagglutinin. This leads to susceptibility to and, in some more severe cases, mortality from infections early in childhood. There has also been detected combined immunodeficiency in some patients

Patients with CHH often have increased predispositions to malignancies.

Treatment is symptomatic, often addressing indicators associated with peripheral pulmonary artery stenosis. Laryngotracheal calcification resulting in dyspnea and forceful breathing can be treated with bronchodilators including the short and long-acting β2-agonists, and various anticholinergics. Prognosis is good, yet life expectancy depends on the severity and extent of diffuse pulmonary and arterial calcification.

Mandibuloacral dysplasia is a rare autosomal recessive syndrome characterized by mandibular hypoplasia, delayed cranial suture closure, dysplastic clavicles, abbreviated and club-shaped terminal phalanges, acroosteolysis, atrophy of the skin of the hands and feet, and typical facial changes.

Types include:

Congenital malformations of the dermatoglyphs are a cutaneous condition divided into four main categories based on the appearance of the dermal ridges of which they are composed: (1) ridge aplasia; (2) ridge hypoplasia; (3) ridge dissociation; and (4) ridges-off-the-end.

The incidence is less than 1/1.000.000. Fewer than 50 cases have been reported so far.

Aphalangy, hemivertebrae and urogenital-intestinal dysgenesis is an extremely rare syndrome, described only in three siblings. It associates hypoplasia or aplasia of phalanges of hands and feet, hemivertebrae and various urogenital and/or intestinal abnormalities. Intrafamilial variability is important as one sister had lethal abnormalities (Potter sequence and pulmonary hypoplasia), while her affected brother was in good health with normal psychomotor development at 6 months of age. Prognosis seems to depend mainly on the severity of visceral malformations. Etiology and inheritance remain unknown.

Lenz–Majewski syndrome is a skin condition characterized by hyperostosis, craniodiaphyseal dysplasia, dwarfism, cutis laxa, proximal symphalangism, syndactyly, brachydactyly, mental retardation, enamel hypoplasia, and hypertelorism.

In 2013, whole-exome sequencing showed that a missense mutation resulting in overactive phosphatidylserine synthase 1 was the cause of LMS, making it the first known human disease to be caused by disrupted phosphatidylserine metabolism. The researchers suggested a link between the condition and bone metabolism.

Cartilage–hair hypoplasia (CHH), also known as McKusick type metaphyseal chondrodysplasia, is a rare genetic disorder. It is a highly pleiotropic disorder that clinically manifests by form of short-limbed dwarfism due to skeletal dysplasia, variable level of immunodeficiency and predisposition to malignancies in some cases. It was first reported in 1965 by McKusick et al. Actor Verne Troyer is affected with this form of dwarfism, as was actor Billy Barty, who was renowned for saying "The name of my condition is Cartilage Hair Syndrome Hypoplasia, but you can just call me Billy."

Thymic hypoplasia is a condition where the thymus is underdeveloped or involuted.

Calcium levels can be used to distinguish between the following two conditions associated with thymic hypoplasia:

- 22q11.2 deletion syndrome: hypocalcemia

- Ataxia telangiectasia: normal levels of calcium

Many features of gerodermia osteodysplastica (GO) and another autosomal recessive form of cutis laxa, wrinkly skin syndrome (WSS, ""), are similar to such an extent that both disorders were believed to be variable phenotypes of a single disorder.

Several delineating factors, however, suggest that gerodermia osteodysplastica and wrinkly skin syndrome are distinct entities, but share the same clinic spectrum.

While the prevailing feature of wrinkly, loose skin is more localized with GO, it is usually systemic, yet eases in severity with age during the course of WSS. Also, as the fontanelles ("soft spots") are usually normal on the heads of infants with GO, they are often enlarged in WSS infants.

While WSS is associated with mutations of genes on chromosomes 2, 5, 7, 11 and 14; GO has been linked to mutations in the protein GORAB. A serum sialotransferrin type 2 pattern, also observed with WSS, is not present in GO patients.

But perhaps the most notable feature, differentiating GO from WSS and similar cutis laxa disorders, is the age-specific metaphyseal peg sometimes found in GO-affected long bone, near the knee. Not appearing until around age 4–5, then disappearing by physeal closure, this oddity of bone is thought to represent a specific genetic marker unique to GO and its effects on bone development.

The cause of this condition is not known. A genetic basis is suspected. More than one case have been reported in three families.

At the core of the disorder there is a homozygous or compound heterozygous mutation or deletion of the SHOX (Short Stature Homeobox), SHOXY (Short Stature Homeobox Y-linked) or PAR1 (where SHOX enhancer elements are located) genes, which is inherited in a pseudosomal recessive manner.

Schmitt Gillenwater Kelly syndrome is a rare autosomal dominant congenital disorder consisting of radial hypoplasia, triphalangeal thumbs, hypospadias, and maxillary diastema.

Keutel syndrome (KS) is a rare autosomal recessive genetic disorder characterized by abnormal diffuse cartilage calcification, hypoplasia of the mid-face, peripheral pulmonary stenosis, hearing loss, short distal phalanges (tips) of the fingers and mild mental retardation. Individuals with KS often present with peripheral pulmonary stenosis, brachytelephalangism, sloping forehead, midface hypoplasia, and receding chin. It is associated with abnormalities in the gene coding for matrix gla protein (MGP). Being an autosomal recessive disorder, it may be inherited from two unaffected, abnormal MGP-carrying parents. Thus, people who inherit two affected MGP genes will likely inherit KS.

It was first identified in 1972 as a novel rare genetic disorder sharing similar symptoms with chondrodysplasia punctata. Multiple forms of chondrodysplasia punctata share symptoms consistent with KS including abnormal cartilage calcification, forceful respiration, brachytelephalangism, hypotonia, psychomotor delay, and conductive deafness, yet peripheral pulmonary stenosis remains unique to KS.

No chromosomal abnormalities are reported in affected individuals, suggesting that familial consanguinity relates to the autosomal recessive mode of inheritance. Also, despite largely abnormal calcification of regions including the larynx, tracheobronchial tree, nose, pinna (anatomy), and epiglottis, patients exhibit normal serum calcium and phosphate levels.

Focal dermal hypoplasia has been associated with PORCN gene mutations on the X chromosome. 90% of the individuals who are affected with the syndrome are female: the commonly accepted, though unconfirmed, explanation for this is that the non-mosaic hemizygous males are not viable.

The differential diagnosis of focal dermal hypoplasia (Goltz) syndrome includes autosomal recessive Setleis syndrome due to TWIST2 gene mutations. It associated with morning glory anomaly, polymicrogyria, incontinentia pigmenti, oculocerebrocutaneous syndrome, Rothmund-Thomson syndrome and microphthalmia with linear skin defects (also known as MLS) syndrome because they are all caused by deletions or point mutations in the HCCS gene.

The prognosis of this developmental disorder is highly based on the underlying disorder. Cerebellar hypoplasia may be progressive or static in nature. Some cerebellar hypoplasia resulting from congenital brain abnormalities/malformations are not progressive. Progressive cerebellar hypoplasia is known for having poor prognosis, but in cases where this disorder is static, prognosis is better.

This is rare and is usually due to mutations in the R-spondin 4 (RSPO4) gene which is located on the short arm of chromosome 20 (20p13). Clinically it is manifest by the absence (anonychia) or hypoplasia (hyponuchia) of finger- and/or toenails.

Fleischer's syndrome is an extremely rare congenital anomaly characterized by displacement of the nipples, occasional polymastia, and hypoplasia of both kidneys.

In a newborn boy thought to have Fryns syndrome, Clark and Fenner-Gonzales (1989) found mosaicism for a tandem duplication of 1q24-q31.2. They suggested that the gene for this disorder is located in that region. However, de Jong et al. (1989), Krassikoff and Sekhon (1990), and Dean et al. (1991) found possible Fryns syndrome associated with anomalies of chromosome 15, chromosome 6, chromosome 8(human)and chromosome 22, respectively. Thus, these cases may all represent mimics of the mendelian syndrome and have no significance as to the location of the gene for the recessive disorder.

By array CGH, Slavotinek et al. (2005) screened patients with DIH and additional phenotypic anomalies consistent with Fryns syndrome for cryptic chromosomal aberrations. They identified submicroscopic chromosome deletions in 3 probands who had previously been diagnosed with Fryns syndrome and had normal karyotyping with G-banded chromosome analysis. Two female infants were found to have microdeletions involving 15q26.2 (see 142340), and 1 male infant had a deletion in band 8p23.1 (see 222400).

Gerodermia osteodysplastica (GO), also called geroderma osteodysplasticum and Walt Disney dwarfism, is a rare autosomal recessive connective tissue disorder included in the spectrum of cutis laxa syndromes.

Usage of the name "Walt Disney dwarfism" is attributed to the first known case of the disorder, documented in a 1950 journal report, in which the authors described five affected members from a Swiss family as having the physical appearance of dwarves from a Walt Disney film.

The terms "geroderma" or "gerodermia" can be used interchangeably with "osteodysplastica" or "osteodysplasticum", with the term "hereditaria" sometimes appearing at the end.

Focal dermal hypoplasia (also known as "Goltz syndrome") is a form of ectodermal dysplasia. It is a multisystem disorder characterized primarily by skin manifestations to the atrophic and hypoplastic areas of skin which are present at birth. These defects manifest as yellow-pink bumps on the skin and pigmentation changes. The disorder is also associated with shortness of stature and some evidence suggests that it can cause epilepsy.

Pigmented hairy epidermal nevus syndrome is a cutaneous condition characterized by a Becker nevus, ipsilateral hypoplasia of the breast, and skeletal defects such as scoliosis.

Ulnar–mammary syndrome or Schinzel syndrome is a cutaneous condition characterized by nipple and breast hypoplasia or aplasia.

It has been associated with TBX3.

Presence of inner ear abnormalities lead to Delayed gross development of child because of balance impairment and profound deafness which increases the risk of trauma and accidents.

- Incidence of accidents can be decreased by using visual or vibrotactile alarm systems in homes as well as in schools.

- Anticipatory education of parents, health providers and educational programs about hazards can help.

Facial femoral syndrome is a rare congenital disorder. It is also known as femoral dysgenesis, bilateral femoral dysgenesis, bilateral-Robin anomaly and femoral hypoplasia-unusual facies syndrome. The main features of this disorder are underdeveloped thigh bones (femurs) and unusual facial features.