{"frequencyBands":{"HP:0040280":[100,100],"HP:0040281":[80,99],"HP:0040282":[30,79],"HP:0040283":[5,29],"HP:0040284":[1,4],"HP:0040285":[0,0]},"page":{"columns":[{"gene":"","key":"MONDO:0014487/OMIM:616084","label":"Sideroblastic anemia with B-cell immunodeficiency, periodic fevers, and developmental delay","mondoId":"MONDO:0014487","onsetQualifier":null,"recordKeys":["07e72ac395400fb7d20982ace5f0184cdcb5c5e678db103ef0492e2422ee08ae","08371968179a252fbca6cde4f8eec893d8e815cfa06d522e4a0633a25f88ad8d","1b8e38615f4f04f01f871d170e1ab3c48c49e79cbe8dc3b7973be27b7802b49c","1eea97dee7a3f6dc69ab7d0dcea86c30ad34f67f112e30ce98c7732d351507f4","2c9da315dd6ce79fabed142a2f53c3f5380233d0cc4a6c3910e561cf2534a8b3","46c210d1fed5f841b38a48c8695e497fdb6eaf130b840f606dfb7145616e0ceb","53acdd5ee70f70ecd7d512faebdbeca739934147cecf21855e71760af801d2f9","56d0165ab59e1399833475d4696d1e94259da35f0185ed7db33afbd1a89883ba","5ab73496a498d209d967f894ebb630820f7bae013c5b25c8a43bc839c3c91d94","5b26fcec2c568c757a638e87a19219e390b35505c4fe81cb71d9b8071ca8d715","6b53369818a32399bc68a1c5eb9182776b19ae38371874973f30b532cc992741","7700e8681c89b6d37d1fc2bfd689aa10ce417f7d580dcca5e8dafe57ae5c9af8","7efa93bc2406944d39d49660bf3bc5c180a0d9dbeca056e723efdffe0bfcdb5e","7ffc676933d978a482fa27a1fe12846802f129b6ce08c8921ef7a086d8f8bcf4","835a16b29fb6e7c2946c2eb1da0dcc3ff4934d29694df00bcdd3f88e3358a63a","91d6c7bab2f563fdea2cc5fc7e2132448a4d84bd02dfffb6fb46c9acdda30757","99f5bea9fc56ff028024456a3b07d93d485392c9fd9db9b6edde1d966aa99250","a575c7d8cb83e45afcf0e1d49d7398ce5a7666a4f128ae2dc7de72dbb4294c74","af84003095449e31cf6198547ff2cbe2ed7b4bc728b0dd6730c1b2b24f773514","bd0b1cecbdd4d5269328473d24e35b7f1523ced8d418d21ab5f577e7ab59ddec","ce680824bc96cc116501ad13b8b1762a35585d94270f8d9bca1dea938c942176","d96767e22359d64a34300737261b22bd7ac829137a284f26d03e7b933febd94e","f2aac38958a91f90dd21de38ca10ac94dc7c3c20adf317c7b2cb40ae3f9f6df0","f2e948479d5a0e629eb967f4e4670f105c4407af0c1cb1f1ede9fcb9309b34c4","fce716ef9b69dc3e4dd5d84715d7d075258039fefb50f146685bfe03d4c6d916"],"recordQualifiers":{},"scopeLabel":"OMIM:616084","sourceIds":["OMIM:616084"],"sourceScope":"This column retains the native source entry. It is not a pooled estimate for the umbrella condition."}],"comparison":{"collapseColumnsLabel":"Show initial comparisons","defaultColumnKeys":["MONDO:0014487/OMIM:616084"],"expandColumnsLabel":"Compare all source entries","intro":"Compare the original source entries. Different entries may describe different patient groups.","primaryFeatureIds":[],"scopeNoteHtml":"<p>Each column keeps its native condition scope. Initial features are displayed alphabetically, not ranked by clinical importance. Counts remain separate, and an empty cell does not mean a feature cannot occur.</p>"},"coverage":{"countRecords":17,"emptyColumnKeys":[],"hpoRelease":"2026-06-23","narrativeSourceChanges":[],"records":25,"sourceGroups":{"omim":0,"orphanet":0,"published":25}},"features":[{"hpoId":"HP:0003355","label":"Aminoaciduria","primary":false},{"hpoId":"HP:0001251","label":"Ataxia (coordination difficulty)","primary":false},{"hpoId":"HP:0008936","label":"Axial hypotonia","primary":false},{"hpoId":"HP:0002299","label":"Brittle hair","primary":false},{"hpoId":"HP:0001638","label":"Cardiomyopathy","primary":false},{"hpoId":"HP:0002059","label":"Cerebral atrophy","primary":false},{"hpoId":"HP:0001334","label":"Communicating hydrocephalus","primary":false},{"hpoId":"HP:0004313","label":"Decreased circulating immunoglobulin concentration","primary":false},{"hpoId":"HP:0010976","label":"Decreased total B cell count","primary":false},{"hpoId":"HP:0002188","label":"Delayed CNS myelination","primary":false},{"hpoId":"HP:0002194","label":"Delayed gross motor development","primary":false},{"hpoId":"HP:0001290","label":"Generalized hypotonia","primary":false},{"hpoId":"HP:0001263","label":"Global developmental delay","primary":false},{"hpoId":"HP:0001510","label":"Growth delay","primary":false},{"hpoId":"HP:0004840","label":"Hypochromic microcytic anemia","primary":false},{"hpoId":"HP:0001252","label":"Hypotonia","primary":false},{"hpoId":"HP:0003128","label":"Lactic acidosis","primary":false},{"hpoId":"HP:0000121","label":"Nephrocalcinosis","primary":false},{"hpoId":"HP:0032323","label":"Periodic fever","primary":false},{"hpoId":"HP:0000510","label":"Rod-cone dystrophy","primary":false},{"hpoId":"HP:0001981","label":"Schistocytosis","primary":false},{"hpoId":"HP:0001250","label":"Seizures","primary":false},{"hpoId":"HP:0000407","label":"Sensorineural hearing loss","primary":false},{"hpoId":"HP:0001924","label":"Sideroblastic anemia","primary":false},{"hpoId":"HP:0001744","label":"Splenomegaly","primary":false}],"ledeHtml":"TRNT1 deficiency is a condition that affects many body systems. Its signs and symptoms can involve blood cells, the immune system, the eyes, and the nervous system. The severity of the signs and symptoms vary widely.","mondoId":"MONDO:0014487","records":[{"frequencyKind":"count","key":"07e72ac395400fb7d20982ace5f0184cdcb5c5e678db103ef0492e2422ee08ae","raw":{"aspect":"P","body_system":"skin","disease_id":"OMIM:616084","disease_name":"Sideroblastic anemia with B-cell immunodeficiency, periodic fevers, and developmental delay","evidence":"PCS","frequency_raw":"3/3","hpo_id":"HP:0002299","is_excluded":false,"label":"Brittle hair","onset_id":null,"reference":"PMID:23553769","source_release":"2026-06-23"},"sourceGroups":["published"]},{"frequencyKind":"count","key":"08371968179a252fbca6cde4f8eec893d8e815cfa06d522e4a0633a25f88ad8d","raw":{"aspect":"P","body_system":"nervous_system","disease_id":"OMIM:616084","disease_name":"Sideroblastic anemia with B-cell immunodeficiency, periodic fevers, and developmental delay","evidence":"PCS","frequency_raw":"4/12","hpo_id":"HP:0002059","is_excluded":false,"label":"Cerebral atrophy","onset_id":null,"reference":"PMID:23553769","source_release":"2026-06-23"},"sourceGroups":["published"]},{"frequencyKind":"count","key":"1b8e38615f4f04f01f871d170e1ab3c48c49e79cbe8dc3b7973be27b7802b49c","raw":{"aspect":"P","body_system":"metabolic","disease_id":"OMIM:616084","disease_name":"Sideroblastic anemia with B-cell immunodeficiency, periodic fevers, and developmental delay","evidence":"PCS","frequency_raw":"3/4","hpo_id":"HP:0003128","is_excluded":false,"label":"Lactic acidosis","onset_id":null,"reference":"PMID:23553769","source_release":"2026-06-23"},"sourceGroups":["published"]},{"frequencyKind":"count","key":"1eea97dee7a3f6dc69ab7d0dcea86c30ad34f67f112e30ce98c7732d351507f4","raw":{"aspect":"P","body_system":"blood","disease_id":"OMIM:616084","disease_name":"Sideroblastic anemia with B-cell immunodeficiency, periodic fevers, and developmental delay","evidence":"PCS","frequency_raw":"12/12","hpo_id":"HP:0001924","is_excluded":false,"label":"Sideroblastic anemia","onset_id":"HP:0003593","reference":"PMID:23553769","source_release":"2026-06-23"},"sourceGroups":["published"]},{"frequencyKind":"count","key":"2c9da315dd6ce79fabed142a2f53c3f5380233d0cc4a6c3910e561cf2534a8b3","raw":{"aspect":"P","body_system":"blood","disease_id":"OMIM:616084","disease_name":"Sideroblastic anemia with B-cell immunodeficiency, periodic fevers, and developmental delay","evidence":"PCS","frequency_raw":"11/12","hpo_id":"HP:0010976","is_excluded":false,"label":"Decreased total B cell count","onset_id":null,"reference":"PMID:23553769","source_release":"2026-06-23"},"sourceGroups":["published"]},{"frequencyKind":"count","key":"46c210d1fed5f841b38a48c8695e497fdb6eaf130b840f606dfb7145616e0ceb","raw":{"aspect":"P","body_system":"nervous_system","disease_id":"OMIM:616084","disease_name":"Sideroblastic anemia with B-cell immunodeficiency, periodic fevers, and developmental delay","evidence":"PCS","frequency_raw":"11/12","hpo_id":"HP:0001263","is_excluded":false,"label":"Global developmental delay","onset_id":null,"reference":"PMID:23553769","source_release":"2026-06-23"},"sourceGroups":["published"]},{"frequencyKind":"reported","key":"53acdd5ee70f70ecd7d512faebdbeca739934147cecf21855e71760af801d2f9","raw":{"aspect":"P","body_system":"nervous_system","disease_id":"OMIM:616084","disease_name":"Sideroblastic anemia with B-cell immunodeficiency, periodic fevers, and developmental delay","evidence":"PCS","frequency_raw":null,"hpo_id":"HP:0002194","is_excluded":false,"label":"Delayed gross motor development","onset_id":null,"reference":"PMID:23553769","source_release":"2026-06-23"},"sourceGroups":["published"]},{"frequencyKind":"reported","key":"56d0165ab59e1399833475d4696d1e94259da35f0185ed7db33afbd1a89883ba","raw":{"aspect":"P","body_system":"musculoskeletal","disease_id":"OMIM:616084","disease_name":"Sideroblastic anemia with B-cell immunodeficiency, periodic fevers, and developmental delay","evidence":"PCS","frequency_raw":null,"hpo_id":"HP:0008936","is_excluded":false,"label":"Axial hypotonia","onset_id":null,"reference":"PMID:23553769","source_release":"2026-06-23"},"sourceGroups":["published"]},{"frequencyKind":"count","key":"5ab73496a498d209d967f894ebb630820f7bae013c5b25c8a43bc839c3c91d94","raw":{"aspect":"P","body_system":"metabolic","disease_id":"OMIM:616084","disease_name":"Sideroblastic anemia with B-cell immunodeficiency, periodic fevers, and developmental delay","evidence":"PCS","frequency_raw":"7/9","hpo_id":"HP:0003355","is_excluded":false,"label":"Aminoaciduria","onset_id":null,"reference":"PMID:23553769","source_release":"2026-06-23"},"sourceGroups":["published"]},{"frequencyKind":"count","key":"5b26fcec2c568c757a638e87a19219e390b35505c4fe81cb71d9b8071ca8d715","raw":{"aspect":"P","body_system":"nervous_system","disease_id":"OMIM:616084","disease_name":"Sideroblastic anemia with B-cell immunodeficiency, periodic fevers, and developmental delay","evidence":"PCS","frequency_raw":"1/12","hpo_id":"HP:0002188","is_excluded":false,"label":"Delayed CNS myelination","onset_id":null,"reference":"PMID:23553769","source_release":"2026-06-23"},"sourceGroups":["published"]},{"frequencyKind":"reported","key":"6b53369818a32399bc68a1c5eb9182776b19ae38371874973f30b532cc992741","raw":{"aspect":"P","body_system":"immune","disease_id":"OMIM:616084","disease_name":"Sideroblastic anemia with B-cell immunodeficiency, periodic fevers, and developmental delay","evidence":"PCS","frequency_raw":null,"hpo_id":"HP:0004313","is_excluded":false,"label":"Decreased circulating immunoglobulin concentration","onset_id":null,"reference":"PMID:23553769","source_release":"2026-06-23"},"sourceGroups":["published"]},{"frequencyKind":"reported","key":"7700e8681c89b6d37d1fc2bfd689aa10ce417f7d580dcca5e8dafe57ae5c9af8","raw":{"aspect":"P","body_system":"blood","disease_id":"OMIM:616084","disease_name":"Sideroblastic anemia with B-cell immunodeficiency, periodic fevers, and developmental delay","evidence":"PCS","frequency_raw":null,"hpo_id":"HP:0001981","is_excluded":false,"label":"Schistocytosis","onset_id":null,"reference":"PMID:23553769","source_release":"2026-06-23"},"sourceGroups":["published"]},{"frequencyKind":"reported","key":"7efa93bc2406944d39d49660bf3bc5c180a0d9dbeca056e723efdffe0bfcdb5e","raw":{"aspect":"P","body_system":"metabolic","disease_id":"OMIM:616084","disease_name":"Sideroblastic anemia with B-cell immunodeficiency, periodic fevers, and developmental delay","evidence":"PCS","frequency_raw":null,"hpo_id":"HP:0032323","is_excluded":false,"label":"Periodic fever","onset_id":null,"reference":"PMID:23553769","source_release":"2026-06-23"},"sourceGroups":["published"]},{"frequencyKind":"count","key":"7ffc676933d978a482fa27a1fe12846802f129b6ce08c8921ef7a086d8f8bcf4","raw":{"aspect":"P","body_system":"blood","disease_id":"OMIM:616084","disease_name":"Sideroblastic anemia with B-cell immunodeficiency, periodic fevers, and developmental delay","evidence":"PCS","frequency_raw":"12/12","hpo_id":"HP:0004840","is_excluded":false,"label":"Hypochromic microcytic anemia","onset_id":null,"reference":"PMID:23553769","source_release":"2026-06-23"},"sourceGroups":["published"]},{"frequencyKind":"count","key":"835a16b29fb6e7c2946c2eb1da0dcc3ff4934d29694df00bcdd3f88e3358a63a","raw":{"aspect":"P","body_system":"nervous_system","disease_id":"OMIM:616084","disease_name":"Sideroblastic anemia with B-cell immunodeficiency, periodic fevers, and developmental delay","evidence":"PCS","frequency_raw":"1/12","hpo_id":"HP:0001334","is_excluded":false,"label":"Communicating hydrocephalus","onset_id":null,"reference":"PMID:23553769","source_release":"2026-06-23"},"sourceGroups":["published"]},{"frequencyKind":"count","key":"91d6c7bab2f563fdea2cc5fc7e2132448a4d84bd02dfffb6fb46c9acdda30757","raw":{"aspect":"P","body_system":"genitourinary","disease_id":"OMIM:616084","disease_name":"Sideroblastic anemia with B-cell immunodeficiency, periodic fevers, and developmental delay","evidence":"PCS","frequency_raw":"3/7","hpo_id":"HP:0000121","is_excluded":false,"label":"Nephrocalcinosis","onset_id":null,"reference":"PMID:23553769","source_release":"2026-06-23"},"sourceGroups":["published"]},{"frequencyKind":"count","key":"99f5bea9fc56ff028024456a3b07d93d485392c9fd9db9b6edde1d966aa99250","raw":{"aspect":"P","body_system":"digestive","disease_id":"OMIM:616084","disease_name":"Sideroblastic anemia with B-cell immunodeficiency, periodic fevers, and developmental delay","evidence":"PCS","frequency_raw":"4/11","hpo_id":"HP:0001744","is_excluded":false,"label":"Splenomegaly","onset_id":null,"reference":"PMID:23553769","source_release":"2026-06-23"},"sourceGroups":["published"]},{"frequencyKind":"count","key":"a575c7d8cb83e45afcf0e1d49d7398ce5a7666a4f128ae2dc7de72dbb4294c74","raw":{"aspect":"P","body_system":"ear","disease_id":"OMIM:616084","disease_name":"Sideroblastic anemia with B-cell immunodeficiency, periodic fevers, and developmental delay","evidence":"PCS","frequency_raw":"5/11","hpo_id":"HP:0000407","is_excluded":false,"label":"Sensorineural hearing impairment","onset_id":null,"reference":"PMID:23553769","source_release":"2026-06-23"},"sourceGroups":["published"]},{"frequencyKind":"count","key":"af84003095449e31cf6198547ff2cbe2ed7b4bc728b0dd6730c1b2b24f773514","raw":{"aspect":"P","body_system":"cardiovascular","disease_id":"OMIM:616084","disease_name":"Sideroblastic anemia with B-cell immunodeficiency, periodic fevers, and developmental delay","evidence":"PCS","frequency_raw":"2/9","hpo_id":"HP:0001638","is_excluded":false,"label":"Cardiomyopathy","onset_id":null,"reference":"PMID:23553769","source_release":"2026-06-23"},"sourceGroups":["published"]},{"frequencyKind":"count","key":"bd0b1cecbdd4d5269328473d24e35b7f1523ced8d418d21ab5f577e7ab59ddec","raw":{"aspect":"P","body_system":"nervous_system","disease_id":"OMIM:616084","disease_name":"Sideroblastic anemia with B-cell immunodeficiency, periodic fevers, and developmental delay","evidence":"PCS","frequency_raw":"4/9","hpo_id":"HP:0001251","is_excluded":false,"label":"Ataxia","onset_id":null,"reference":"PMID:23553769","source_release":"2026-06-23"},"sourceGroups":["published"]},{"frequencyKind":"reported","key":"ce680824bc96cc116501ad13b8b1762a35585d94270f8d9bca1dea938c942176","raw":{"aspect":"P","body_system":"musculoskeletal","disease_id":"OMIM:616084","disease_name":"Sideroblastic anemia with B-cell immunodeficiency, periodic fevers, and developmental delay","evidence":"PCS","frequency_raw":null,"hpo_id":"HP:0001290","is_excluded":false,"label":"Generalized hypotonia","onset_id":null,"reference":"PMID:23553769","source_release":"2026-06-23"},"sourceGroups":["published"]},{"frequencyKind":"count","key":"d96767e22359d64a34300737261b22bd7ac829137a284f26d03e7b933febd94e","raw":{"aspect":"P","body_system":"nervous_system","disease_id":"OMIM:616084","disease_name":"Sideroblastic anemia with B-cell immunodeficiency, periodic fevers, and developmental delay","evidence":"PCS","frequency_raw":"5/12","hpo_id":"HP:0001250","is_excluded":false,"label":"Seizure","onset_id":null,"reference":"PMID:23553769","source_release":"2026-06-23"},"sourceGroups":["published"]},{"frequencyKind":"count","key":"f2aac38958a91f90dd21de38ca10ac94dc7c3c20adf317c7b2cb40ae3f9f6df0","raw":{"aspect":"P","body_system":"eye","disease_id":"OMIM:616084","disease_name":"Sideroblastic anemia with B-cell immunodeficiency, periodic fevers, and developmental delay","evidence":"PCS","frequency_raw":"3/6","hpo_id":"HP:0000510","is_excluded":false,"label":"Rod-cone dystrophy","onset_id":null,"reference":"PMID:23553769","source_release":"2026-06-23"},"sourceGroups":["published"]},{"frequencyKind":"range","key":"f2e948479d5a0e629eb967f4e4670f105c4407af0c1cb1f1ede9fcb9309b34c4","raw":{"aspect":"P","body_system":"growth","disease_id":"OMIM:616084","disease_name":"Sideroblastic anemia with B-cell immunodeficiency, periodic fevers, and developmental delay","evidence":"PCS","frequency_raw":"HP:0040283","hpo_id":"HP:0001510","is_excluded":false,"label":"Growth delay","onset_id":null,"reference":"PMID:23553769","source_release":"2026-06-23"},"sourceGroups":["published"]},{"frequencyKind":"reported","key":"fce716ef9b69dc3e4dd5d84715d7d075258039fefb50f146685bfe03d4c6d916","raw":{"aspect":"P","body_system":"musculoskeletal","disease_id":"OMIM:616084","disease_name":"Sideroblastic anemia with B-cell immunodeficiency, periodic fevers, and developmental delay","evidence":"PCS","frequency_raw":null,"hpo_id":"HP:0001252","is_excluded":false,"label":"Hypotonia","onset_id":null,"reference":"PMID:23553769","source_release":"2026-06-23"},"sourceGroups":["published"]}],"referenceLabels":{},"references":{"causeHtml":"<ul><li><a href=\"https://medlineplus.gov/genetics/condition/trnt1-deficiency\">TRNT1 deficiency</a></li></ul>","identityNote":"MONDO cross-references identify native condition entries. Ancestor membership does not transfer phenotype values between groups.","importantHtml":""},"sections":[{"bodyHtml":"<p>TRNT1 deficiency is caused by mutations in the TRNT1 gene, which provides instructions for making a protein involved in the production (synthesis) of other proteins. During protein synthesis, a molecule called transfer RNA (tRNA) helps assemble protein building blocks (amino acids) into a chain that forms the protein. Each tRNA carries a specific amino acid to the growing chain. The TRNT1 protein modifies tRNAs, which allows the correct amino acid to be attached to each tRNA.</p><p>TRNT1 gene mutations lead to a shortage (deficiency) of functional TRNT1 protein. As a result, modification of tRNA molecules is impaired. Without the modification, tRNAs are thought to be less able to participate in protein synthesis. Researchers suspect that protein synthesis in cellular structures called mitochondria, which are the energy-producing centers of cells, is most strongly affected. The resulting decrease in energy production may damage cells in many body systems, leading to the varied signs and symptoms of TRNT1 deficiency. Researchers believe that mutations that cause a greater impairment of TRNT1 function lead to more severe signs and symptoms.</p><p class=\"section-source\"><a href=\"https://medlineplus.gov/genetics/condition/trnt1-deficiency/#causes\">MedlinePlus Genetics: Causes</a></p>","key":"forms","title":"What causes TRNT1 deficiency?"},{"bodyHtml":"<p>A common feature of TRNT1 deficiency is a blood condition called sideroblastic anemia, which is characterized by a shortage of red blood cells (anemia). In TRNT1 deficiency, the red blood cells that are present are unusually small (erythrocytic microcytosis). In addition, developing red blood cells in the bone marrow (erythroblasts) can have an abnormal buildup of iron that appears as a ring of blue staining in the cell after treatment in the lab with certain dyes. These abnormal cells are called ring sideroblasts.</p><p>Many people with TRNT1 deficiency have an immune system disorder (immunodeficiency) that can lead to recurrent bacterial infections. Repeated infections can cause life-threatening damage to internal organs. The immunodeficiency is characterized by low numbers of immune system cells called B cells, which normally help fight infections by producing immune proteins called antibodies (or immunoglobulins). These proteins target foreign invaders such as bacteria and viruses and mark them for destruction. In many individuals with TRNT1 deficiency, the amount of immunoglobulins is also low (hypogammaglobulinemia).</p><p>In addition, many individuals with TRNT1 deficiency have recurrent fevers that are not caused by an infection. These fever episodes are often one of the earliest recognized symptoms of TRNT1 deficiency, usually beginning in infancy. The fever episodes are typically accompanied by poor feeding, vomiting, and diarrhea, and can lead to hospitalization. In many affected individuals, the episodes occur regularly, arising approximately every 2 to 4 weeks and lasting 5 to 7 days, although the frequency can decrease with age.</p><p>Eye abnormalities, often involving the light-sensing tissue at the back of the eye (the retina), can occur in people with TRNT1 deficiency. Some of these individuals have a condition called retinitis pigmentosa, in which the light-sensing cells of the retina gradually deteriorate. Eye problems in TRNT1 deficiency can lead to vision loss.</p><p>Neurological problems are also frequent in TRNT1 deficiency. Many affected individuals have delayed development of speech and motor skills, such as sitting, standing, and walking, and some have low muscle tone (hypotonia).</p><p>Features that occur less commonly in people with TRNT1 deficiency include hearing loss caused by abnormalities of the inner ear (sensorineural hearing loss), recurrent seizures (epilepsy), and problems with the kidneys or heart.</p><p>TRNT1 deficiency encompasses what was first thought to be two separate disorders, a severe disorder called sideroblastic anemia with B-cell immunodeficiency, periodic fevers, and developmental delay (SIFD) and a milder disorder called retinitis pigmentosa with erythrocytic microcytosis (RPEM), each named for its most common features. SIFD begins in infancy, and affected individuals usually do not survive past childhood. RPEM, on the other hand, is recognized in early adulthood, and the microcytosis usually does not cause any health problems. However, it has since been recognized that some individuals have a combination of features that fall between these two ends of the severity spectrum. All of these cases are now considered part of TRNT1 deficiency.</p><p class=\"section-source\">Source: <a href=\"https://medlineplus.gov/genetics/condition/trnt1-deficiency\">MedlinePlus Genetics</a></p>","key":"overview","title":"Condition overview"}],"sharedSources":[],"slug":"trnt1-deficiency","sourceDocuments":[{"name":"TRNT1 deficiency","reviewed":"2017-11","sections":{"causes":{"fetchedAt":"2026-10-20T20:25:34.958614+00:00","label":"Causes","pageSha256":"c1561e7e37c91ab7bd1bb05374c77df9166999e7213bc11a2fa8c90c13518ef2","sourceUrl":"https://medlineplus.gov/genetics/condition/trnt1-deficiency/#causes","status":"available"}},"source_release":"2026-10-01","url":"https://medlineplus.gov/genetics/condition/trnt1-deficiency"}],"sourceNote":"MedlinePlus descriptions and Causes; original HPO annotations.","takeawayHtml":"Cause explanations are from MedlinePlus Genetics. Feature values below retain their original sources and patient groups.","title":"TRNT1 deficiency"},"schemaVersion":1}