Nager syndrome is an inherited disorder characterized by defects to the face, limbs and hands. Babies born with this condition typically exhibit down-slanted palpebral fissures as well as an eyelid coloboma (notch in their lower eyelid).
Missing or malformed thumbs, fingers that are unusually bent (clinodactyly), short forearms that cannot extend fully at the elbows; all of this are characteristic features of this condition caused by mutations to SF3B4 gene.
Symptoms
Nager Syndrome, a genetic condition caused by mutation of the SF3B4 gene that regulates bone and cartilage formation, affects head and neck structures such as jaws, ears and limbs; fingers may bend in clinodactyly (clinodactyly); webbed or crooked feet may occur as well as webbed hands and webbed feet; though usually unaffectful intelligence-wise but may delay speech development due to hearing loss associated with this condition.
An initial step to diagnosing Nager syndrome in your child involves conducting a physical examination, with healthcare providers looking for specific symptoms of the disorder as well as ordering X-rays to observe how bones develop in his or her face, legs and arms. Blood samples will also be taken for laboratory analysis to check if they contain the gene mutation responsible.
Autosomal dominant inheritance patterns apply when it comes to Nager syndrome, meaning one of your child’s biological parents must carry the mutation for it to pass down to them. However, most cases of Nager syndrome are sporadic; meaning the mutation occurred spontaneously in one egg or sperm without impacting any other family members.
Treatment for Nager syndrome includes corrective surgery to address problems with your child’s jaws, ears and limbs. This might involve correcting any cleft palates or lips; adjusting underdevelopment of jaw; improving sloped eyes; or even preventing further deterioration in limbs and thumb. Your child may require a tracheostomy or gastrostomy in order to create an opening in their throat and insert a tube for easier breathing. They may require a thyroplasty procedure in order to address their underdevelopment of thumb by harvesting tendon or muscle from another part of their body and inserting it back into its original position – this would correct their issue with their thumb. Some children with Nager syndrome exhibit physical features such as scoliosis or shortened forearms with restricted elbow range of motion. Other children may suffer from heart conditions, gastrointestinal disorders or genital defects that necessitate psychosocial input for the whole family – including counseling sessions and support groups.
Diagnosis
Nager Syndrome can be diagnosed through physical examination, X-rays and echocardiography (an ultrasound of the heart). Affected individuals may display kidney, genitalia and/or urinary tract abnormalities. An abnormality in the SF3B4 gene causes this condition – only one parent needs to carry this gene mutation for it to pass down; autosomal recessive inheritance occurs here.
Medical geneticists specialize in genetic conditions and can quickly and accurately diagnose Nager syndrome with a physical exam and blood sample sent for testing at a laboratory; there the mutated gene responsible can be identified in their blood cells.
Infants born with this disorder may require tube feedings and tracheotomies in order to breathe effectively, as well as difficulties moving their arms and legs. Their fingers may fuse together or appear bent (clinodactyly), and their forearms could become shorter due to partial or total absence of the radius bone.
Surgical treatment may help address many of the symptoms experienced by those living with this condition. Pollicization involves replacing one thumb with tendon or muscle taken from another part of the body; or altogether removing it. Surgery can also correct talipes equinovarus – an abnormality affecting both feet and lower legs – through its corrective effect on this disorder.
Others surgeries can improve the function of one’s head and face, including corrective surgeries for cleft lip/palate defects or to enhance hearing. People living with this disorder may have poor facial expressions that can be improved using various techniques such as soft palate prostheses.
Due to the various complications of this condition, a multidisciplinary team should coordinate a person’s care. This team may include craniofacial surgeons, plastic surgeons, otolaryngologists (ear, nose and throat doctors), pediatricians, dentists, orthodontists, audiologists (hearing specialists), speech and language therapists and geneticists; it may even be coordinated at a center dedicated solely to these conditions – the goal being achieving the best outcomes for those living with this disorder.
Treatment
Nager syndrome is an inherited disorder caused by mutations to the SF3B4 gene, which controls proteins responsible for various physical processes. Mutations may interfere with their production and result in abnormalities to bones and facial features.
Nager syndrome is a genetic condition which impairs the development of both first and second pharyngeal arches early during gestation. These structures play a crucial role in facial and neck development, including nerves which control expressions and chewing movements. Other parts affected include eyes, jaw and ears – children living with Nager syndrome often exhibit underdeveloped jaws and eyes leading to breathing issues; their ears may either be completely missing (microtia) or very small with inadequate development (atresia).
Aberrations may also lead to issues in the arms and hands. People living with this condition often display malformed thumbs (clinodactyly or syndactyly), as well as having reduced forearm length due to missing bone fragments called radius bones.
People living with this condition also often exhibit abnormalities in the bones of their feet, including flat feet that tend to turn inward (club foot), feet that resemble spoon shapes (pes planus), or an unusually short bone in their ankle called the tibia. Clinodactyly may also occur.
Nager Syndrome does not have a definitive treatment, but medical treatments may provide significant relief of its symptoms. Treatment should ideally take place at a center that employs multidisciplinary approaches; such teams would ideally include maxillofacial surgeons, plastic surgeons, ear, nose, and throat specialists as well as pediatricians and geneticists.
An essential step for those suffering from Nager syndrome is keeping in touch with their doctor, to receive appropriate medical treatment and keep conditions from worsening. Good oral hygiene and eating a low-sugar diet will also help protect against dental decay or any other issues in the mouth, but remember to schedule regular check-ins with your physician and follow any instructions they give you.
Preventative measures
Nager syndrome is an inherited disorder that alters how your child’s face and hands develop. It’s caused by mutations (changes) to the SF3B4 gene which codes for spliceosomal proteins; other genes have also been implicated. Autosomal dominant inheritance patterns typically play out here – meaning one copy of a gene with mutation is enough to cause disease symptoms.
Symptoms of Nager syndrome often emerge during childhood and include underdeveloped cheek bones (malar hypoplasia); micrognathia; an opening in the roof of the mouth (cleft palate); abnormally small, elongated or malformed external ears (pinnae). Some individuals affected may also have short upper arm bones (radial ray aplasia) or missing thumbs.
By choosing not to have children, you could possibly reduce the likelihood of your offspring inheriting this condition. Unfortunately, however, this won’t guarantee them protection since any family members with mutations of SF3B4 genes could pass it along to future offspring.
Healthcare providers will examine your newborn shortly after birth and order X-rays of his or her head and neck, in addition to taking blood samples in order to screen for mutations in SF3B4 gene.
If your child has this condition, they may require gastrostomy feedings or an airway device such as tracheotomy to help them breathe properly.
People living with Nager syndrome require care from a multidisciplinary team of specialists. This should include craniofacial surgeons, pediatric otolaryngologists, plastic surgeons, orthodontists, ophthalmologists and audiologists.
As people with Nager syndrome can have various complications, they must receive extensive treatment and follow-up. This typically begins in neonatal period and continues for up to 20 years of age; and may include surgical correction for cleft palate, sloped eyes, underdeveloped lower jaw; reconstructing cheekbones; repairing ear defects; as well as physiotherapy to enhance quality of life and increase function and quality of life – sometimes this leads to improved functioning or quality of life depending on severity of symptoms which interfere with breathing or eating functions.