CONDITION REFERENCE
Benign familial neonatal seizures
Information from MedlinePlus Genetics about this condition and how it can be inherited.
About this condition
Benign familial neonatal seizures (BFNS) is a condition characterized by recurrent seizures in newborn babies. The seizures begin around day 3 of life and usually go away within 1 to 4 months. The seizures can involve only one side of the brain (focal seizures) or both sides (generalized seizures). This condition is often associated with generalized tonic-clonic seizures (also known as grand mal seizures). This type of seizure involves both sides of the brain and affects the entire body, causing a combination of seizure types: tonic seizures, which are characterized by uncontrolled muscle stiffness and rigidity, and clonic seizures, which are characterized by uncontrolled jerking of the muscles. Seizure episodes in infants with BFNS typically begin with tonic stiffness and pauses in breathing (apnea) followed by clonic jerking.
A test called an electroencephalogram (EEG) is used to measure the electrical activity of the brain. Abnormalities on an EEG test, measured during no seizure activity, can indicate a risk for seizures. However, infants with BFNS usually have normal EEG readings. In some affected individuals, the EEG shows a specific abnormality called the theta pointu alternant pattern. By age 2, most affected individuals who had EEG abnormalities have a normal EEG reading.
Typically, seizures are the only symptom of BFNS, and most people with this condition develop normally. However, some affected individuals develop intellectual disability that becomes noticeable in early childhood. A small percentage of people with BFNS also have a condition called myokymia, which is an involuntary rippling movement of the muscles. In addition, in about 15 percent of people with BFNS, recurrent seizures (epilepsy) will come back later in life after the seizures associated with BFNS have gone away. The age that epilepsy begins is variable.
Inheritance
- Autosomal dominant
A condition can have several forms with different inheritance patterns. Each pattern may apply to a different gene or form of the condition.
Related genes
MedlinePlus lists these genes for this condition. Open a gene page to read any available ClinGen reviews and ClinVar records.
YOUR DNA FILE
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Sources and dates
The source information on this page last changed on 2026-09-18.
MedlinePlus Source details
Source release: Fri, 18 Sep 2026 05:17:13 GMT
Source publication: 2023-08-17
Source review: 2011-05
SHA-256: fdc8bd614310c12718379cef6569962e5d0e791cecabcc355b53a72816ac263a
About the library sources · Latest validated release · Record 8a91308d513a