Exome sequencing identified a novel missense mutation c.464G>A (p.G155D) in Ca2+-binding protein 4 (CABP4) in a Chinese pedigree with autosomal dominant nocturnal frontal lobe epilepsy.
It has been demonstrated that CHRFAM7A is expressed in CD4+ T-lymphocytes of healthy individuals, the relative abundance of the transcript being nearly equal (about 100 copies per cell), but it is not expressed in ADNFLE patients.
Although over hundred families are on record, only a minority of them have been linked to mutations in the genes coding for the alpha4, alpha2 and beta2 (CHRNA4, CHRNA2, and CHRNB2) subunits of the nAChRs, indicating that ADNFLE is genetically heterogeneous despite a relatively homogeneous clinical picture.
In order to assess the genetic defects in NFLE, we performed a mutation screening in 33 unrelated patients with sporadic NFLE by amplifying and sequencing bidirectionally TM 1-3 of CHRNA4, CHRNB2 and CHRNA2 which contain the mutations reported in ADNFLE.
Autosomal dominant nocturnal frontal lobe epilepsy (ADNFLE) is partly caused by mutations in the nicotinic acetylcholine receptor (nAChR) genes CHRNA4, CHRNB2, and CHRNA2.
Certain mutations in specific parts of the neuronal nicotinic acetylcholine receptor (nAChR) subunit genes CHRNA4, CHRNB2, and probably CHRNA2, can cause autosomal dominant nocturnal frontal lobe epilepsy (ADNFLE).
Autosomal dominant nocturnal frontal lobe epilepsy (ADNFLE; MIM 600513) has been associated with mutations in the genes coding for the alfa-4 (CHRNA4), beta-2 (CHRNB2), and alpha-2 (CHRNA2) subunits of the neuronal nicotinic acetylcholine receptor (nAChR) and for the corticotropin-releasing hormone (CRH).
Even if nicotinic acetylcholine receptor genes are traditionally associated with autosomal dominant nocturnal frontal lobe epilepsy (ADNFLE), this single-family description can open new possibilities in the genetic diagnosis, molecular characterization, and management of CHRNA2-related epilepsy.
Analyses of functional properties of four nAChR mutants associated with ADNFLE indicate that a gain of function of these mutant receptors may be at the origin of the neuronal network dysfunction that causes the epileptic seizures.
As a result of this finding, other subunits of the neuronal nAChR gene family are being considered as candidate genes for ADNFLE in families not linked to CHRNA4 and for other idiopathic epilepsies.
Mutations responsible for autosomal dominant nocturnal frontal lobe epilepsy have been identified in two members of the neuronal nicotinic acetylcholine receptor gene family: CHRNA4(ENFL1 locus) and CHRNB2 (ENFL3 locus) coding for alpha4 and beta2 subunit, respectively.
In 1999, Hirose et al. reported a Japanese family with autosomal dominant nocturnal frontal lobe epilepsy (ADNFLE) associated with a neuronal nicotinic acetylcholine receptor α4 subunit mutation (S252L).
A missense mutation in the neuronal nicotinic acetylcholine receptor alpha 4 subunit is associated with autosomal dominant nocturnal frontal lobe epilepsy.
DNAs from 20 representative affected individuals were sequenced in order to check for the presence of the missense mutation in the CHRNA4 gene found in the Australian kindred affected by ADNFLE.
Recently, two different mutations of the neuronal nicotinic acetylcholine receptor alpha4 subunit (CHRNA4) gene were identified in a white family as a cause of ADNFLE.
We have assessed nAChR distribution in eight non-smoking ADNFLE patients (from five families) bearing an identified mutation in nAChRs and in seven age-matched non-smoking healthy volunteers using PET and [(18)F]-F-A-85380.