Question: What is (are) Achondrogenesis ?
Answer: Achondrogenesis is a group of severe disorders that are present from birth and affect the development of cartilage and bone. Infants with achondrogenesis usually have a small body, short arms and legs, and other skeletal abnormalities that cause life-threatening complications. There are at least three forms of achondrogenesis, type 1A, type 1B and type 2, which are distinguished by signs and symptoms, pattern of inheritance, and the results of imaging studies such as x-rays (radiology), tissue analysis (histology), and genetic testing. Type 1A and 1B achondrogenesis are both inherited in an autosomal recessive pattern. Type 1B may be caused by mutations in the SLC26A2 gene. Type 2 achondrogenesis is inherited in an autosomal dominant pattern and is caused by new (de novo) mutations in the COL2A1 gene.
Source: GARD

Question: What are the symptoms of Achondrogenesis ?
Answer: What are the signs and symptoms of Achondrogenesis? The Human Phenotype Ontology provides the following list of signs and symptoms for Achondrogenesis. If the information is available, the table below includes how often the symptom is seen in people with this condition. You can use the MedlinePlus Medical Dictionary to look up the definitions for these medical terms. Signs and Symptoms Approximate number of patients (when available) Abnormality of bone mineral density 90% Anteverted nares 90% Aplasia/Hypoplasia of the lungs 90% Brachydactyly syndrome 90% Frontal bossing 90% Hydrops fetalis 90% Long philtrum 90% Macrocephaly 90% Malar flattening 90% Micromelia 90% Narrow chest 90% Short neck 90% Short nose 90% Short stature 90% Short thorax 90% Short toe 90% Skeletal dysplasia 90% Thickened nuchal skin fold 90% Abnormality of the ribs 50% Polyhydramnios 50% Recurrent fractures 50% Talipes 50% Umbilical hernia 50% Cystic hygroma 7.5% Postaxial hand polydactyly 7.5% Abdominal distention - Abnormal foot bone ossification - Abnormal hand bone ossification - Abnormality of the femoral metaphysis - Abnormality of the foot - Absent or minimally ossified vertebral bodies - Absent vertebral body mineralization - Autosomal dominant inheritance - Autosomal recessive inheritance - Barrel-shaped chest - Beaded ribs - Breech presentation - Broad clavicles - Broad long bones - Cleft palate - Decreased skull ossification - Depressed nasal bridge - Disproportionate short-limb short stature - Disproportionate short-trunk short stature - Edema - Flat face - Horizontal ribs - Hypoplasia of the radius - Hypoplastic ilia - Hypoplastic iliac wing - Hypoplastic ischia - Hypoplastic scapulae - Inguinal hernia - Neonatal short-limb short stature - Protuberant abdomen - Respiratory insufficiency - Short clavicles - Short long bone - Short ribs - Short tubular bones (hand) - Stillbirth - Unossified vertebral bodies - The Human Phenotype Ontology (HPO) has collected information on how often a sign or symptom occurs in a condition. Much of this information comes from Orphanet, a European rare disease database. The frequency of a sign or symptom is usually listed as a rough estimate of the percentage of patients who have that feature. The frequency may also be listed as a fraction. The first number of the fraction is how many people had the symptom, and the second number is the total number of people who were examined in one study. For example, a frequency of 25/25 means that in a study of 25 people all patients were found to have that symptom. Because these frequencies are based on a specific study, the fractions may be different if another group of patients are examined. Sometimes, no information on frequency is available. In these cases, the sign or symptom may be rare or common.
Source: GARD

Question: What causes Achondrogenesis ?
Answer: What causes achondrogenesis? Research has shown that changes (mutations) in the SLC26A2 and COL2A1 genes cause achondrogenesis types 1B and 2, respectively. The genetic cause of achondrogenesis type 1A remains unknown. The SLC26A2 gene provides instructions for making a protein that is important for the normal development of cartilage and for the conversion of cartilage to bone. The COL2A1 gene provides instructions for making a protein that forms a type of collagen found mostly in cartilage and in the clear gel that fills the eyeball (vitreous). Mutations in these genes result in the production of proteins that are unable to properly perform their jobs within the body.
Source: GARD

Question: Is Achondrogenesis inherited ?
Answer: How is achondrogenesis inherited? Achondrogenesis type 1A and type 1B are believed to be inherited in an autosomal recessive pattern. Autosomal recessive inheritance means both copies of the gene in each cell have mutations. Most often, the parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but do not show signs and symptoms of the condition. 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. It is almost always caused by new (de novo) mutations and typically occurs in people with no history of the disorder in their family.
Source: GARD

Question: How to diagnose Achondrogenesis ?
Answer: Is genetic testing is available for achondrogenesis? Genetic testing can help distinguish between the different types of achondrogenesis. GeneTests lists the names of laboratories that are performing genetic testing for achondrogenesis type 1B and type 2. Please note: Most of the laboratories listed through GeneTests do not accept direct contact from patients and their families; therefore, if you are interested in learning more, you will need to work with a health care provider or a genetics professional. In the Services tab, we provide a list of online resources that can assist you in locating a genetics professional near you.
Source: GARD