Phenotypes associated with the disease hereditary intrinsic factor deficiency (OMIM:261000):
- Decreased circulating haptoglobin concentration (HP:0020181): The concentration of haptoglobin in the blood circulation is below the lower limit of normal. Evidence: PCS. Frequency: 1/1. (PMID:14576042)
- Paresthesia (HP:0003401): Abnormal sensations such as tingling, pricking, or numbness of the skin with no apparent physical cause. Evidence: IEA. (OMIM:261000)
- Juvenile onset (HP:0003621): Onset of signs or symptoms of disease between the age of 5 and 15 years. Evidence: IEA. (OMIM:261000)
- Malabsorption of Vitamin B12 (HP:0200118). Evidence: PCS. Frequency: 1/1. (PMID:14576042)
- Somatic sensory dysfunction (HP:0003474): An abnormality of the primary sensation that is mediated by peripheral nerves (pain, temperature, touch, vibration, joint position). The word hypoesthesia (or hypesthesia) refers to a reduction in cutaneous sensation to a specific type of testing. Evidence: IEA. (OMIM:261000)
- Increased RBC distribution width (HP:0031965): Red blood cell distribution width (RDW) is a simple parameter of the standard full blood count and a measure of heterogeneity in the size of circulating erythrocytes. It is provided by automated hematology analyzers and it reflects the range of the red cell size. It is calculated by dividing the standard deviation of erythrocyte volume by the mean corpuscular volume (MCV) and multiplied by 100 to convert to a percentage. Evidence: PCS. Frequency: 1/1. (PMID:14576042)
- Decreased circulating vitamin B12 concentration (HP:0100502): The concentration of vitamin B12 in the blood circulation is below the lower limit of normal. Evidence: PCS. Frequency: 1/1. (PMID:14576042)
- Childhood onset (HP:0011463): Onset of disease at the age of between 1 and 5 years. Evidence: PCS. Frequency: 1/1. (PMID:14576042)
- Megaloblastic anemia (HP:0001889): Anemia characterized by the presence of erythroblasts that are larger than normal (megaloblasts). Evidence: PCS. Frequency: 1/1. (PMID:14576042)
- Autosomal recessive inheritance (HP:0000007): A mode of inheritance that is observed for traits related to a gene encoded on one of the autosomes (i.e., the human chromosomes 1-22) in which a trait manifests in individuals with two pathogenic alleles, either homozygotes (two copies of the same mutant allele) or compound heterozygotes (whereby each copy of a gene has a distinct mutant allele). Evidence: PCS. (PMID:14576042)
- Increased mean corpuscular volume (HP:0005518): Larger than normal size of erythrocytes. Evidence: IEA. (OMIM:261000)
- Increased circulating lactate dehydrogenase concentration (HP:0025435): An elevated level of the enzyme lactate dehydrogenase in the blood circulation. Evidence: PCS. Frequency: 1/1. (PMID:14576042)
- Megaloblastic erythroid hyperplasia (HP:0200143). Evidence: TAS. (OMIM:261000)
- Absence of intrinsic factor (HP:0005219): Absence of gastric intrinsic factor, which is normally produced by the parietal cells of the stomach, and is required for the absorption of vitamin B12. Evidence: PCS. Frequency: 1/1. (PMID:14576042)