Table 2

History and examination findings for individual KCNJ11 case and INS control subjects

Case subject (mutation)HistoryExamination/investigations
Developmental milestones/ interventionsSeizures (cause, if known)Educational attainmentLearning difficulties/supportEmployment status (job)Employment status (job) of parents/siblingsPsychiatric historyNeurological examinationBrain MRI
KCNJ11 1 (G53S)D (speech and motor)NoMS then SS (age 11)LS (repeated year 2)E (supermarket)F – E (council), S – E (chemicals factory)Repetitive handwashing and rigid routinesImpaired motor sequencing, fine finger movements, praxis. Subtle nystagmus, dysdiadokokinesisND
KCNJ11 2 (R201H)D (speech)NoMS then U (nursing and childcare)LS (English until age 15 years, math for 1 year)USF – E (accountant), M – E (nurse)NilIntermittent mild head titubation. Brisk reflexes, questionable increase in tone in left armN
KCNJ11 3 (R201H)NYes: hypoglycemia on insulinMS then C (18 months, NVQs levels 1 and 2)LS (English and math)E (baker)NKNilNormalBilateral high T1 signal in pons, artifact
KCNJ11 4 (R201C)NYesMS then C (computing module)LS (throughout school)E (pubs, shops, hotel)B – E (operations manager), S – E (sports complex manager)Depression: sertraline 50 mg. Occasional auditory hallucinationsNystagmus (2–3 beats on horizontal gaze), subtle intention tremorN
KCNJ11 5 (R201C)D (gross motor, speech). Speech therapyYes: hypoglycemia on insulinMS then C (for people with ID)LS (from age 10 years)CS (college for people with ID)F – E (company manager), M – UE (housewife), B – E (aviation engineer), B – US (political science)Anxiety (social skills training by psychologist)Impaired motor sequencingND
KCNJ11 6 (V252G)D (speech, fine motor). Speech therapyNoSS then school for autistic childrenUnable to read/write. Supported accommodationUEB – E (carpenter)AutismImpaired motor sequencing, praxis, heel-toe walking. Hand flappingND
KCNJ11 7 (V59M)Speech therapyYes: hypoglycemia on insulinMS then C (1st year - childcare)LS (throughout school)E (SS teaching assistant)M – E (SS teaching assistant), F – E (lecturer), B – E (trainee lawyer)AnxietyImpaired motor sequencing, dysdiadokokinesis, choreiform movementsN (movement artifact)
KCNJ11 8 (V59M)D (global)Yes: hypoglycemia on insulinSSUnable to read/writeUES – E (museum curator)AutismRitualistic, clumsy, echolalia. Generally uncooperative with examinationND
INS 1 (C43F)NYesU (pharmacy degree)NoE (hospital pharmacist)NKNilNND
INS 2 (F48C)NYes: hypoglycemiaU (law degree)No supportUE (ill health). Clerical/caregiver jobs in pastF – E (taxi business manager, security guard)Depression (medication and CBT in the past), OCDDepressed leg reflexes (in keeping with known diabetic neuropathy)Left temporal lobe abnormality, CSF space or artifact
INS 3 (G75C)NNoMSNo supportE (department of work and pensions)F – E (carpenter, transport manager), B – E (marketing agency)NilNN
INS 4 (H29D)NYes: DKAMSLS (math and English, 4 years)E (bank call center)F – E (carpenter)Anxiety, panic attacks (escitalopram in the past)NProminent left cerebellar sulcus, periventricular white matter lesions
  • B, brother; C, college; CBT, cognitive behavioral therapy; CS, college student; D, delayed; DKA, diabetic ketoacidosis; E, employed; F, father; ID, intellectual disability; LS, learning support; M, mother; MS, mainstream school; N, normal; ND, not done; NK, not known; OCD, obsessive compulsive disorder; S, sister; SS, special school; U, university; UE, unemployed; US, university student.