Anemia, and Myoclonus

Ss blood group antigens reside on the red-cell glycoprotein GYPB. The S and s antigens result from a polymorphism at amino acid 29 of GYPB, where S has met29 and s has thr29. The U antigen refers to a short extracellular sequence in GYPB located near the membrane. GYPB, glycophorin A (GYPA ), and glycophorin E (GYPE ) are closely linked on chromosome 4q31. Antigens of the MN blood group (OMIM ) reside on GYPA. The M and N antigens differ at amino acids 1 and 5 of GYPA, where M is ser-ser-thr-thr-gly, and N is leu-ser-thr-thr-glu. The N terminus of GYPB is essentially identical to that of GYPA except that it always expresses the N antigen, denoted 'N' or N-prime. Recombination and gene conversion between GYPA, GYPB, and GYPE lead to hybrid glycophorin molecules and generation of low-incidence antigens. Thus, the MN and Ss blood groups are together referred to as the MNSs blood group system (see {111300}). Recombination results in 3 glycophorin-null phenotypes: En(a-) cells lack GYPA due to recombination between GYPA and GYPB; GYPB-negative (S-s-U-) cells lack GYPB due to recombination in GYPB; and M(k) cells (M-N-S-s-U-) lack both GYPA and GYPB due to recombination between GYPA and GYPE. Individuals with glycophorin-null phenotypes have decreased sialic acid content and increased resistance to malarial infection (see {611162}). GYPA and GYPB are not essential for red-cell development or survival, and GYPA- and GYPB-null phenotypes are not associated with anemia or altered red-cell function (review by Cooling, 2015).

BLOOD GROUP, SS; SS Is also known as ss blood group

• Neoplasm
• Anemia

SOURCES: OMIM MENDELIAN

general increase in bulk of a muscle due to an increase in cell volume; it is not due to tumor formation, nor to an increase in the number of cells.

• Myoclonus
• Skeletal muscle hypertrophy

SOURCES: OMIM ORPHANET MENDELIAN

Action myoclonus-renal failure syndrome (AMRF) is a rare epilepsy syndrome characterized by progressive myoclonus epilepsy in association with primary glomerular disease. Patients present with neurologic symptoms (including tremor, action myoclonus, tonic-clonic seizures, later ataxia and dysarthria) that may precede, occur simultaneously or be followed by renal manifestations including proteinuria that progresses to nephrotic syndrome and end-stage renal disease. In some patients, sensorimotor peripheral neuropathy, sensorineural hearing loss and dilated cardiomyopathy are associated symptoms.

ACTION MYOCLONUS-RENAL FAILURE SYNDROME Is also known as myoclonus-nephropathy syndrome|progressive myoclonic epilepsy type 4|epm4|amrf|action myoclonus-renal failure syndrome

• Seizures
• Ataxia
• Anemia
• Peripheral neuropathy
• Dysarthria

SOURCES: ORPHANET OMIM MENDELIAN

Paroxysmal exertion-induced dyskinesia (PED) is a form of paroxysmal dyskinesia (see this term), characterized by painless attacks of dystonia of the extremities triggered by prolonged physical activities.

PAROXYSMAL EXERTION-INDUCED DYSKINESIA Is also known as ped with or without epilepsy and/or hemolytic anemia|paroxysmal exertion-induced dystonia with or without epilepsy and/or hemolytic anemia|dyt18|dystonia 18|ped|paroxysmal exercise-induced dyskinesia with or without epilepsy and/or hemolytic anemia

• Intellectual disability
• Seizures
• Global developmental delay
• Generalized hypotonia
• Microcephaly

SOURCES: ORPHANET OMIM MESH MENDELIAN

Rolandic epilepsy (RE) is a focal childhood epilepsy characterized by seizures consisting of unilateral facial sensory-motor symptoms, with electroencephalogram (EEG) showing sharp biphasic waves over the rolandic region. It is an age-related epilepsy, with excellent outcome.

ROLANDIC EPILEPSY Is also known as becrs|bre|benign rolandic epilepsy|bects|centrotemporal epilepsy|benign epilepsy of childhood with centrotemporal spikes|benign familial epilepsy of childhood with rolandic spikes

• Intellectual disability
• Seizures
• Global developmental delay
• Microcephaly
• Abnormal facial shape

SOURCES: ORPHANET OMIM MENDELIAN

• Seizures
• Ataxia
• Anemia
• Dysarthria
• Tremor

SOURCES: OMIM MESH ORPHANET MENDELIAN

Dihydrofolate reductase deficiency is an autosomal recessive metabolic disorder characterized by the hematologic findings of megaloblastic anemia and variable neurologic symptoms, ranging from severe developmental delay and generalized seizures in infancy (Banka et al., 2011) to childhood absence epilepsy with learning difficulties to lack of symptoms (Cario et al., 2011). Treatment with folinic acid can ameliorate some of the symptoms.

CONSTITUTIONAL MEGALOBLASTIC ANEMIA WITH SEVERE NEUROLOGIC DISEASE Is also known as dihydrofolate reductase deficiency|dhfr deficiency

• Seizures
• Global developmental delay
• Generalized hypotonia
• Microcephaly
• Ataxia

SOURCES: ORPHANET OMIM MESH MENDELIAN

Hematologically, McLeod syndrome is characterized by the absence of red blood cell Kx antigen, weak expression of Kell red blood cell antigens, acanthocytosis, and compensated hemolysis. Most carriers of this McLeod blood group phenotype have acanthocytosis and elevated serum creatine kinase levels and are prone to develop a severe neurologic disorder resembling Huntington disease (OMIM ). Onset of neurologic symptoms ranges between 25 and 60 years (mean onset 30-40 years), and penetrance appears to be high. Additional symptoms include generalized seizures, neuromuscular symptoms leading to weakness and atrophy, and cardiomyopathy mainly manifesting with atrial fibrillation, malignant arrhythmias, and dilated cardiomyopathy (summary by Jung et al., 2007).The cooccurrence of McLeod syndrome and chronic granulomatous disease (CGD ) results from a contiguous gene deletion (Francke et al., 1985).

MCLEOD SYNDROME; MCLDS Is also known as mcleod phenotype|neuroacanthocytosis, mcleod type

• Seizures
• Muscle weakness
• Cognitive impairment
• Anemia
• Peripheral neuropathy

SOURCES: MESH OMIM MENDELIAN

Neuroblastoma is a malignant tumor of neural crest cells, the cells that give rise to the sympathetic nervous system, which is observed in children.

• Ataxia
• Neoplasm
• Failure to thrive
• Pain
• Anemia

SOURCES: ORPHANET OMIM MENDELIAN

3-hydroxy-3-methylglutaric aciduria (3HMG) is an organic aciduria, due to deficiency of 3-hydroxy-3-methylglutaryl-CoA-lyase (a key enzyme in ketogenesis and leucine metabolism) usually presenting in infancy with episodes of metabolic decompensation triggered by periods of fasting or infections, which when left untreated are life-threatening and may lead to neurological sequelae.

3-HYDROXY-3-METHYLGLUTARIC ACIDURIA Is also known as hydroxymethylglutaric aciduria|hmg-coa lyase deficiency|3-hydroxy-3-methylglutaryl-coa lyase deficiency|hmgcl deficiency|hl deficiency

• Seizures
• Global developmental delay
• Generalized hypotonia
• Spasticity
• Anemia

SOURCES: ORPHANET MESH OMIM MENDELIAN