Benign familial neonatal seizures

Last updated
Benign familial neonatal epilepsy [1]
Other namesBenign familial neonatal convulsions
Specialty Neurology   OOjs UI icon edit-ltr-progressive.svg

Benign familial neonatal seizures (BFNS), also referred to as benign familial neonatal epilepsy (BFNE), is a rare autosomal dominant inherited form of seizures. This condition manifests in newborns as brief and frequent episodes of tonic-clonic seizures with asymptomatic periods in between. [2] Characteristically, seizure activity spontaneously ends during infancy and does not affect childhood development. [2] [3] However, some studies have reported that a minority of children with BFNS consequently develop intellectual disability. [3] Additionally, BFNS increases lifetime susceptibility to seizures as approximately 14% of those afflicted go on to develop epilepsy later in life. [4] There are three known genetic causes of BFNE, two being the voltage-gated potassium channels KCNQ2 (BFNC1) and KCNQ3 (BFNC2) and the third being a chromosomal inversion (BFNC3). There is no obvious correlation between most of the known mutations and clinical variability seen in BFNE.

Contents

Signs and symptoms

BNFS often presents in the first week of life with brief but frequent episodes of tonic-clonic seizures, outside of which a child is completely asymptomatic. [2] [3] [4] During the tonic phase of these seizures, infants may stop breathing (apnea) and consequently appear blue (cyanosis) due to lack of oxygen. Accompanying this is focal or generalized muscle stiffening. [2] [3] [4] The clonic phase usually follows, during which the infant may make noises, display focal or multi-focal rhythmic jerking of the body, and/or display abnormal eye and facial movement. [2] [3] [4] Characteristically, testing for seizures between episodes with EEG is normal. However, the appearance of a “theta pointu alternant pattern” and/or non-specific abnormalities on EEG has been reported in several cases, although their relationship to BFNE has not been well delineated. [2] These seizure episodes resolve entirely within days to weeks, and in most patients have no effects on neurodevelopment. [2] [3] [4] With that said, several studies tracking the health of patients with BFNE into adulthood have reported consequent intellectual disability [3] and seizure disorders. [4]

Pathophysiology

BFNC1

The most prevalent known cause of BFNE is mutation of KCNQ2, a gene encoding a voltage-gated potassium channel (KV7.2). There are at least 35 such mutations, see Table 1, primarily located in the voltage sensitive S4 segment through the C-terminus. Of these mutations, 5 are nonsense mutations, 13 are missense mutations and 11 cause a frameshift in the coding sequence. There are also 5 splice variants, one of which has been characterized at the protein level and leads to a nonsense mutation. Finally, there is one large deletion that removes much of the carboxy-terminus of the channel.

While most BFNC1 mutations have not been further characterized, 14 have and all seem to lead to functional defects. Two of the mutations in the voltage-sensitive S4 segment, R207W and R214W, do not lead to a decrease in the whole-cell current (M current) produced by KCNQ2 channels but to a change in channel kinetics. The R207W mutation takes fourfold longer and the R214W mutation takes twofold longer to reach maximal current compared to wild-type channels. [5] Since the time-course of an action potential is shorter than the time required for mutant KCNQ2 channels to reach proper levels of inactivation these mutants are expected to lead to neuronal hyperexcitability.

Though many of the other characterized mutations lead to decreased whole-cell current that has not been further delineated, three mutations have. Y534fsX538, for example, leads to a truncation that removes much of the carboxy-terminus of the channel. This mutant has been studied and shown to not traffic properly to the membrane. [6] Two other mutations, P709fs929X and W867fsX931, lead to altered carboxy-termini, though they actually lengthen rather than truncate the protein. These abnormal extended proteins have been shown to be more rapidly degraded within cells and, thus, produce little current. [7]

Table 1. Mutations in KCNQ2 associated with BFNE
MutationRegionFunctional ConsequenceReferences
Nucleotide Amino acid
c.232delCQ78fsX132N-Terminus [8]
c.314_316delCCTS105CfsX872S1 [8]
c.387+1G→T Splicing S2 [9]
c.584_593del10insAS195XS4 [10]
c.C587T+c.T590CA196V+L197PS4 [11]
c.C619TR207WS4Slowed activation [5]
c.G622AM208VS4Current decreased by ~50% [9]
c.C641TR214WS4Slowed activation and increased deactivation [5] , [12] , [13]
c.C674GH228QS4-S5 [9]
c.T727CL243FS5 [9]
c.C740GS247WS5No current and dominant negative [9]
c.G807AW269XPore [9]
c.848_849insGTK283fsX329Pore [9] , [14]
c.A851GY284CPoreCurrent decreased by ~50% [6] , [9] , [13] , [14] , [15]
c.G916AA306TS6Current decreased by ~80% [6] , [9] , [14] , [15]
c.C967TQ323XC-TerminusCurrent reduction by ~50% [9]
c.G998AR333QC-TerminusCurrent reduction by ~40% [9]
c.T1016GR339LC-Terminus [11]
c.1118+1G→A Splicing C-Terminus [8]
c.Intron 8_3' UTR delDeletion 382→3' UTR C-Terminus [9] , [14]
c.1217+2T→G Splicing C-Terminus [16]
c.C1342TR448XC-TerminusCurrent reduction by ~40% [9] , [11]
c.1369_1370delAAK457EfsX458C-Terminus [17]
c.1564_1576delS522fsX524C-Terminus [9] , [14]
c.1600_1601insGCCCTY534fsX538C-TerminusNo current due to no trafficking [6] , [15] , [18]
c.1630-1G→A Splicing C-Terminus [9] , [14]
c.G1658AR553QC-Terminus [11]
c.G1662T* K554NC-TerminusDecreased voltage sensitivity of activation [19]
c.C1741TR581XC-Terminus [9]
c.1764-6C→A Splicing (V589X)C-Terminus [20]
c.1931delGS644TfsX901(extX56)C-Terminus [21]
c.1959del?T653fsX929(extX56)C-Terminus [9]
c.2127delTP709fs929X(extX57)C-TerminusNo current due to increased degradation [7] , [22] , [23]
c.2597delGG866AfsX929(extX56)C-TerminusCurrent decreased by ~95% due to increased degradation [7] , [22] , [24]
c.2599_2600insGGGCCW867fsX931(extX58)C-TerminusCurrent reduction by ~75% [9]
* Misreported (twice in the same article) as G1662A (G1620A in the original numbering), which would not cause an amino acid change.
N.B. Mutations nucleotide/amino acid positions in terms of transcript variant 1 (NM_172107) available from PubMed. Consequently, some mutation positions differ from those reported in the original literature.

BFNC2

Shortly after the discovery of mutations in KCNQ2 related to BFNE, a novel voltage-gated potassium channel was found that is highly homologous to KCNQ2 and contains mutations also associated with BFNE. This gene, KCNQ3, contains 3 known mutations associated with BFNE, all within the pore region of the channel. The first of these mutations, G310V, leads to a 50% reduction in whole-cell current compared to cells expressing wild-type channels. [9] [15] [25] The reason for this change is unknown as the mutation does not lead to altered protein trafficking. [6]

A second mutation, W309G, has also been found to be associated with BFNE. This mutation was only found in one family and has not been further characterized. [26]

The final known BFNC2 mutation, D305G is also in the pore region of the channel. This mutation leads to an approximately 40% reduction in whole-cell current compared to wild-type expressing cells. The underlying mechanism for this current decrease has not been further delineated. [9]

BFNC3

The rarest cause of BFNE, occurring in only one known family, is a chromosomal inversion. This occurs on chromosome 5 and the inversion is of the p15 through q11 area. Affected individuals, thus, have the karyotype 46,XY,inv(5)(p15q11). Why this inversion leads to the BFNE phenotype is unknown. [27]

Management

Generally speaking, Neonatal seizures are often controlled with phenobarbital administration. While phenobarbital can be used for symptomatic treatment of BFNC, several studies have shown favorable response to anti-seizure medications that specifically block sodium channels (see article on Sodium channel blocker). [2] However, at this time, phenobarital is the first line therapy for BFNC. [2] Recurrent seizures later in life are treated in the standard ways (covered in the main epilepsy article). Depending on the severity, some infants are sent home with heart and oxygen monitors that are hooked to the child with stick on electrodes to signal any seizure activity. Once a month the monitor readings are downloaded into a central location for the doctor to be able to read at a future date. This monitor is only kept as a safeguard as usually the medication wards off any seizures. Once the child is weaned off the phenobarbital, the monitor is no longer necessary.

History

BFNE was first described in 1964 by Andreas Rett [28] and named by Bjerre and Corelius four years later. [29] [30] Andreas Rett is better known for his later characterization of Rett syndrome. [23] Both studies were published in German, but have yet to be translated in English. [30] The mutations associated with BFNE were first mapped and descripted by Leppert and colleagues in 1989. [31]

Related Research Articles

A convulsion is a medical condition where the body muscles contract and relax rapidly and repeatedly, resulting in uncontrolled shaking. Because epileptic seizures typically include convulsions, the term convulsion is often used as a synonym for seizure. However, not all epileptic seizures result in convulsions, and not all convulsions are caused by epileptic seizures. Non-epileptic convulsions have no relation with epilepsy, and are caused by non-epileptic seizures.

Familial hemiplegic migraine (FHM) is an autosomal dominant type of hemiplegic migraine that typically includes weakness of half the body which can last for hours, days, or weeks. It can be accompanied by other symptoms, such as ataxia, coma, and paralysis. Migraine attacks may be provoked by minor head trauma. Some cases of minor head trauma in patients with hemiplegic migraine can develop into delayed cerebral edema, a life-threatening medical emergency. Clinical overlap occurs in some FHM patients with episodic ataxia type 2 and spinocerebellar ataxia type 6, benign familial infantile epilepsy, and alternating hemiplegia of childhood.

Sudden unexpected death in epilepsy (SUDEP) is a fatal complication of epilepsy. It is defined as the sudden and unexpected, non-traumatic and non-drowning death of a person with epilepsy, without a toxicological or anatomical cause of death detected during the post-mortem examination.

Episodic ataxia (EA) is an autosomal dominant disorder characterized by sporadic bouts of ataxia with or without myokymia. There are seven types recognized but the majority are due to two recognized entities. Ataxia can be provoked by psychological stress or startle, or heavy exertion, including exercise. Symptoms can first appear in infancy. There are at least six loci for EA, of which 4 are known genes. Some patients with EA also have migraine or progressive cerebellar degenerative disorders, symptomatic of either familial hemiplegic migraine or spinocerebellar ataxia. Some patients respond to acetazolamide though others do not.

<span class="mw-page-title-main">CDKL5</span> Protein-coding gene in humans

CDKL5 is a gene that provides instructions for making a protein called cyclin-dependent kinase-like 5 also known as serine/threonine kinase 9 (STK9) that is essential for normal brain development. Mutations in the gene can cause deficiencies in the protein. The gene regulates neuronal morphology through cytoplasmic signaling and controlling gene expression. The CDKL5 protein acts as a kinase, which is an enzyme that changes the activity of other proteins by adding a cluster of oxygen and phosphorus atoms at specific positions. Researchers are currently working to determine which proteins are targeted by the CDKL5 protein.

<span class="mw-page-title-main">KvLQT2</span> Protein-coding gene in the species Homo sapiens

Kv7.2 (KvLQT2) is a voltage- and lipid-gated potassium channel protein coded for by the gene KCNQ2.

<span class="mw-page-title-main">KvLQT3</span> Protein-coding gene in the species Homo sapiens

Kv7.3 (KvLQT3) is a potassium channel protein coded for by the gene KCNQ3.

SCN1A Protein-coding gene in the species Homo sapiens

Sodium channel protein type 1 subunit alpha (SCN1A), is a protein which in humans is encoded by the SCN1A gene.

SCN2A Protein-coding gene in the species Homo sapiens

Sodium channel protein type 2 subunit alpha, is a protein that in humans is encoded by the SCN2A gene. Functional sodium channels contain an ion conductive alpha subunit and one or more regulatory beta subunits. Sodium channels which contain sodium channel protein type 2 subunit alpha are sometimes called Nav1.2 channels.

<span class="mw-page-title-main">LGI1</span> Protein-coding gene in the species Homo sapiens

Leucine-rich, glioma inactivated 1, also known as LGI1, is a protein which in humans is encoded by the LGI1 gene. It may be a metastasis suppressor.

<span class="mw-page-title-main">KCNJ10</span> Protein-coding gene in the species Homo sapiens

ATP-sensitive inward rectifier potassium channel 10 is a protein that in humans is encoded by the KCNJ10 gene.

<span class="mw-page-title-main">KCNQ4</span> Mammalian protein found in Homo sapiens

Potassium voltage-gated channel subfamily KQT member 4, also known as voltage-gated potassium channel subunit Kv7.4, is a protein that in humans is encoded by the KCNQ4 gene.

A potassium channel opener is a type of drug which facilitates ion transmission through potassium channels.

M current is a type of noninactivating potassium current first discovered in bullfrog sympathetic ganglion cells.

In molecular biology, the ankyrin-G binding motif of KCNQ2-3 is a protein motif found in the potassium channels KCNQ2 and KCNQ3.

Benign familial infantile epilepsy (BFIE) is an epilepsy syndrome. Affected children, who have no other health or developmental problems, develop seizures during infancy. These seizures have focal origin within the brain but may then spread to become generalised seizures. The seizures may occur several times a day, often grouped in clusters over one to three days followed by a gap of one to three months. Treatment with anticonvulsant drugs is not necessary but they are often prescribed and are effective at controlling the seizures. This form of epilepsy resolves after one or two years, and appears to be completely benign. The EEG of these children, between seizures, is normal. The brain appears normal on MRI scan.

An epilepsy syndrome is defined as "a characteristic cluster of clinical and EEG features, often supported by specific etiological findings ."

A neonatal seizure is a seizure in a baby younger than age 4-weeks that is identifiable by an electrical recording of the brain. It is an occurrence of abnormal, paroxysmal, and persistent ictal rhythm with an amplitude of 2 microvolts in the electroencephalogram,. These may be manifested in form of stiffening or jerking of limbs or trunk. Sometimes random eye movements, cycling movements of legs, tonic eyeball movements, and lip-smacking movements may be observed. Alteration in heart rate, blood pressure, respiration, salivation, pupillary dilation, and other associated paroxysmal changes in the autonomic nervous system of infants may be caused due to these seizures. Often these changes are observed along with the observance of other clinical symptoms. A neonatal seizure may or may not be epileptic. Some of them may be provoked. Most neonatal seizures are due to secondary causes. With hypoxic ischemic encephalopathy being the most common cause in full term infants and intraventricular hemorrhage as the most common cause in preterm infants.

KCNQ2 encephalopathy typically presents with tonic seizures from the first week of life. The seizures can be frequent and often difficult to treat. Seizures can resolve within months or years but can impair the development of several domains such as motor, social, cognitive and language.

<span class="mw-page-title-main">XEN1101</span> Cholesterol 24-hydroxylase inhibitor

XEN1101 (encukalner) is an experimental small molecule anticonvulsant and selective Kv7.2/Kv7.3 potassium channel opener being investigated as a treatment for refractory focal onset seizures and major depressive disorder.

References

  1. Berg AT, Berkovic SF, Brodie MJ, et al. (April 2010). "Revised terminology and concepts for organization of seizures and epilepsies: report of the ILAE Commission on Classification and Terminology, 2005-2009". Epilepsia. 51 (4): 676–85. doi: 10.1111/j.1528-1167.2010.02522.x . PMID   20196795.
  2. 1 2 3 4 5 6 7 8 9 Kannan, Varun; Pareek, Aishwarya V.; Das, Abhijit R.; Gay, Charles T.; Riviello, James J. (September 2023). ""Fifth-day fits" revisited: A literature review of benign idiopathic neonatal seizures and comparison with KCNQ2- and KCNQ3-associated benign familial epilepsy syndromes". Annals of the Child Neurology Society. 1 (3): 202–208. doi: 10.1002/cns3.20039 . ISSN   2831-3267.
  3. 1 2 3 4 5 6 7 Pisani, Francesco; Spagnoli, Carlotta; Falsaperla, Raffaele; Nagarajan, Lakshmi; Ramantani, Georgia (2021-02-01). "Seizures in the neonate: A review of etiologies and outcomes". Seizure. 85: 48–56. doi: 10.1016/j.seizure.2020.12.023 . hdl: 11573/1670082 . ISSN   1059-1311.
  4. 1 2 3 4 5 6 Panayiotopoulos, C. P. (2005), "Neonatal Seizures and Neonatal Syndromes", The Epilepsies: Seizures, Syndromes and Management, Bladon Medical Publishing, retrieved 2023-11-30
  5. 1 2 3 Dedek K, Kunath B, Kananura C, Reuner U, Jentsch T, Steinlein O (2001). "Myokymia and neonatal epilepsy caused by a mutation in the voltage sensor of the KCNQ2 K+ channel". Proceedings of the National Academy of Sciences of the United States of America. 98 (21): 12272–7. Bibcode:2001PNAS...9812272D. doi: 10.1073/pnas.211431298 . PMC   59804 . PMID   11572947.
  6. 1 2 3 4 5 Schwake M, Pusch M, Kharkovets T, Jentsch T (2000). "Surface expression and single channel properties of KCNQ2/KCNQ3, M-type K+ channels involved in epilepsy". J Biol Chem. 275 (18): 13343–8. doi: 10.1074/jbc.275.18.13343 . PMID   10788442.
  7. 1 2 3 Soldovieri M, Castaldo P, Iodice L, Miceli F, Barrese V, Bellini G, Miraglia del Giudice E, Pascotto A, Bonatti S, Annunziato L, Taglialatela M (2006). "Decreased subunit stability as a novel mechanism for potassium current impairment by a KCNQ2 C terminus mutation causing benign familial neonatal convulsions". J Biol Chem. 281 (1): 418–28. doi: 10.1074/jbc.M510980200 . PMID   16260777.
  8. 1 2 3 Claes L, Ceulemans B, Audenaert D, Deprez L, Jansen A, Hasaerts D, Weckx S, Claeys K, Del-Favero J, Van Broeckhoven C, De Jonghe P (2004). "De novo KCNQ2 mutations in patients with benign neonatal seizures". Neurology. 63 (11): 2155–8. doi:10.1212/01.wnl.0000145629.94338.89. PMID   15596769. S2CID   23701482.
  9. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 Singh N, Westenskow P, Charlier C, Pappas C, Leslie J, Dillon J, Anderson V, Sanguinetti M, Leppert M (2003). "KCNQ2 and KCNQ3 potassium channel genes in benign familial neonatal convulsions: expansion of the functional and mutation spectrum". Brain. 126 (Pt 12): 2726–37. doi: 10.1093/brain/awg286 . PMID   14534157.
  10. Bassi M, Balottin U, Panzeri C, Piccinelli P, Castaldo P, Barrese V, Soldovieri M, Miceli F, Colombo M, Bresolin N, Borgatti R, Taglialatela M (2005). "Functional analysis of novel KCNQ2 and KCNQ3 gene variants found in a large pedigree with benign familial neonatal convulsions (BFNC)". Neurogenetics. 6 (4): 185–93. doi:10.1007/s10048-005-0012-2. hdl: 2434/15127 . PMID   16235065. S2CID   23586942.
  11. 1 2 3 4 Moulard B, Picard F, le Hellard S, Agulhon C, Weiland S, Favre I, Bertrand S, Malafosse A, Bertrand D (2001). "Ion channel variation causes epilepsies". Brain Res Brain Res Rev. 36 (2–3): 275–84. doi:10.1016/S0165-0173(01)00104-7. PMID   11690625. S2CID   37406352.
  12. Miraglia del Giudice E, Coppola G, Scuccimarra G, Cirillo G, Bellini G, Pascotto A (2000). "Benign familial neonatal convulsions (BFNC) resulting from mutation of the KCNQ2 voltage sensor". European Journal of Human Genetics. 8 (12): 994–7. doi: 10.1038/sj.ejhg.5200570 . PMID   11175290.
  13. 1 2 Castaldo P, del Giudice E, Coppola G, Pascotto A, Annunziato L, Taglialatela M (2002). "Benign familial neonatal convulsions caused by altered gating of KCNQ2/KCNQ3 potassium channels". J Neurosci. 22 (2): RC199. doi: 10.1523/JNEUROSCI.22-02-j0003.2002 . PMC   6758678 . PMID   11784811.
  14. 1 2 3 4 5 6 Singh N, Charlier C, Stauffer D, DuPont B, Leach R, Melis R, Ronen G, Bjerre I, Quattlebaum T, Murphy J, McHarg M, Gagnon D, Rosales T, Peiffer A, Anderson V, Leppert M (1998). "A novel potassium channel gene, KCNQ2, is mutated in an inherited epilepsy of newborns". Nat Genet. 18 (1): 25–9. doi:10.1038/ng0198-25. PMID   9425895. S2CID   30469895.
  15. 1 2 3 4 Schroeder B, Kubisch C, Stein V, Jentsch T (1998). "Moderate loss of function of cyclic-AMP-modulated KCNQ2/KCNQ3 K+ channels causes epilepsy". Nature. 396 (6712): 687–90. Bibcode:1998Natur.396..687S. doi:10.1038/25367. PMID   9872318. S2CID   4417442.
  16. Lee W, Biervert C, Hallmann K, Tay A, Dean J, Steinlein O (2000). "A KCNQ2 splice site mutation causing benign neonatal convulsions in a Scottish family". Neuropediatrics. 31 (1): 9–12. doi:10.1055/s-2000-15290. PMID   10774989.
  17. Pereira S, Roll P, Krizova J, Genton P, Brazdil M, Kuba R, Cau P, Rektor I, Szepetowski P (2004). "Complete loss of the cytoplasmic carboxyl terminus of the KCNQ2 potassium channel: a novel mutation in a large Czech pedigree with benign neonatal convulsions or other epileptic phenotypes". Epilepsia. 45 (4): 384–90. doi:10.1111/j.0013-9580.2004.47703.x. PMID   15030501. S2CID   9924577.
  18. Biervert C, Schroeder B, Kubisch C, Berkovic S, Propping P, Jentsch T, Steinlein O (1998). "A potassium channel mutation in neonatal human epilepsy". Science. 279 (5349): 403–6. Bibcode:1998Sci...279..403B. doi:10.1126/science.279.5349.403. PMID   9430594.
  19. Borgatti R, Zucca C, Cavallini A, Ferrario M, Panzeri C, Castaldo P, Soldovieri M, Baschirotto C, Bresolin N, Dalla Bernardina B, Taglialatela M, Bassi M (2004). "A novel mutation in KCNQ2 associated with BFNC, drug resistant epilepsy, and mental retardation". Neurology. 63 (1): 57–65. doi:10.1212/01.wnl.0000132979.08394.6d. PMID   15249611. S2CID   26111247.
  20. de Haan G, Pinto D, Carton D, Bader A, Witte J, Peters E, van Erp G, Vandereyken W, Boezeman E, Wapenaar M, Boon P, Halley D, Koeleman B, Lindhout D (2006). "A novel splicing mutation in KCNQ2 in a multigenerational family with BFNC followed for 25 years". Epilepsia. 47 (5): 851–9. doi: 10.1111/j.1528-1167.2006.00552.x . PMID   16686649.
  21. Tang B, Li H, Xia K, Jiang H, Pan Q, Shen L, Long Z, Zhao G, Cai F (2004). "A novel mutation in KCNQ2 gene causes benign familial neonatal convulsions in a Chinese family". J Neurol Sci. 221 (1–2): 31–4. doi:10.1016/j.jns.2004.03.001. PMID   15178210. S2CID   36912785.
  22. 1 2 Coppola G, Castaldo P, Miraglia del Giudice E, Bellini G, Galasso F, Soldovieri M, Anzalone L, Sferro C, Annunziato L, Pascotto A, Taglialatela M (2003). "A novel KCNQ2 K+ channel mutation in benign neonatal convulsions and centrotemporal spikes". Neurology. 61 (1): 131–4. doi:10.1212/01.wnl.0000069465.53698.bd. hdl: 11566/54912 . PMID   12847176. S2CID   29057981.
  23. 1 2 Zimprich F, Ronen G, Stögmann W, Baumgartner C, Stögmann E, Rett B, Pappas C, Leppert M, Singh N, Anderson V (2006). "Andreas Rett and benign familial neonatal convulsions revisited". Neurology. 67 (5): 864–6. doi:10.1212/01.wnl.0000234066.46806.90. PMID   16966552. S2CID   11682106.
  24. Lerche H, Biervert C, Alekov A, Schleithoff L, Lindner M, Klinger W, Bretschneider F, Mitrovic N, Jurkat-Rott K, Bode H, Lehmann-Horn F, Steinlein O (1999). "A reduced K+ current due to a novel mutation in KCNQ2 causes neonatal convulsions". Annals of Neurology. 46 (3): 305–12. CiteSeerX   10.1.1.328.22 . doi:10.1002/1531-8249(199909)46:3<305::AID-ANA5>3.0.CO;2-5. PMID   10482260. S2CID   17711279.
  25. Charlier C, Singh N, Ryan S, Lewis T, Reus B, Leach R, Leppert M (1998). "A pore mutation in a novel KQT-like potassium channel gene in an idiopathic epilepsy family". Nat Genet. 18 (1): 53–5. doi:10.1038/ng0198-53. PMID   9425900. S2CID   10437379.
  26. Hirose S, Zenri F, Akiyoshi H, Fukuma G, Iwata H, Inoue T, Yonetani M, Tsutsumi M, Muranaka H, Kurokawa T, Hanai T, Wada K, Kaneko S, Mitsudome A (2000). "A novel mutation of KCNQ3 (c.925T→C) in a Japanese family with benign familial neonatal convulsions". Annals of Neurology. 47 (6): 822–6. doi:10.1002/1531-8249(200006)47:6<822::AID-ANA19>3.0.CO;2-X. PMID   10852552. S2CID   11096248.
  27. Concolino D, Iembo M, Rossi E, Giglio S, Coppola G, Miraglia Del Giudice E, Strisciuglio P (2002). "Familial pericentric inversion of chromosome 5 in a family with benign neonatal convulsions". J Med Genet. 39 (3): 214–6. doi:10.1136/jmg.39.3.214. PMC   1735071 . PMID   11897828.
  28. Rett A, Teubel R (1964). "Neugeborenenkrämpfe im Rahmen einer epileptisch belasteten Familie". Wien Klin Wochenschr. 74: 609–13.
  29. Bjerre I, Corelius E (1968). "Benign familial neonatal convulsions". Acta Paediatr Scand. 57 (6): 557–61. doi:10.1111/j.1651-2227.1968.tb06980.x. PMID   5706374. S2CID   5144238.
  30. 1 2 Zimprich, F.; Ronen, G. M.; Stögmann, W.; Baumgartner, C.; Stögmann, E.; Rett, B.; Pappas, C.; Leppert, M.; Singh, N.; Anderson, V. E. (2006-09-12). "Andreas Rett and benign familial neonatal convulsions revisited". Neurology. 67 (5): 864–866. doi:10.1212/01.wnl.0000234066.46806.90. ISSN   1526-632X. PMID   16966552.
  31. Leppert, Mark; Anderson, V. Elving; Quattlebaum, T.; Stauffer, Dora; O'Connell, Peter; Nakamura, Yusuke; Lalouel, Jean-Marc; White, Ray (February 1989). "Benign familial neonatal convulsions linked to genetic markers on chromosome 20". Nature. 337 (6208): 647–648. doi:10.1038/337647a0. ISSN   0028-0836. PMID   2918897.