{"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:0024537/OMIM:211530","label":"Brown-Vialetto-Van Laere syndrome 1","mondoId":"MONDO:0024537","onsetQualifier":null,"recordKeys":["003005fcd51bf0659ad3de56b05c2e96a4ab821fc2d8c32f4b6b3375ff992ad8","0c7eeaed4ed9aeafa016bfc57811f199dee670dd44771c3e88bdd672e9cd33c7","20517a1d10c0927094dc0b3637b0a75de413dc0cfb91a5efe8575ba0f841be31","24d0ee57ce02a2a182e5d087ca815cd2b9946d0734ec21925831044ccaf55878","289ebac9a5d402a639bc64302e50d5e6fe4b80aa6bb7db938b8094ef1b486ba3","2cba9c30448f717be3dcbe654bf6d2c58857ef94a1507e436e946eeef1a32d25","36d18a678bd094994099003c36a261c3b29c3de47cfa08db268476a40f2a6b0e","3883469dc97f3880b40248f979c102729b3ed3a767396930f41ea6beaa0973f1","442b08fc26fb548e5f18397f8c9e7bcf9f9db4a529fd9e0e11e9bb754f24d1d1","4d03a58f87da9cf21a917d93ddbf9266f1ea78723720374a39f976f884b894f4","54ebc4b6a853dc6f04dfd910f0cceab53a0b2a68040537d94b6f51d0dfd6a4e6","5bb31a9b1cc8a695df15cfb9ddf7945ef17f5a5defa9e9d9d8b3b783ed595e88","5fe53858587b2513cbbdb309e535f61e96de324a4487df9e49c1f400348c7ebc","60c07a3418482a3be0f293ac25cb31a38794834f50a075a0cd79b98e38c584e7","683e08b2b374758eaca06be7dfa7db45611a18031492bdd7c3915fca6a5110fd","6dfd73a92f7040fe77a3cf475e6052cce5710a4bad282fb65918bd3f5615ef21","7baf5ffc4866a3a93662594c1f82ea689b55ab542baab66a57d90a2c241224a4","7e24af744274ea63f5d0635319daf29ef10246d6a7cf553866274ca39f64007b","807c0f406a515b138138062ae34c5a7110daed8cb4c536f63d2e7139d25633b9","81ad2163e05e7dfd2179e1f6e303069c2969561626646e4b429c52924e884132","847e146c40012c7b4ac8b110866190ba271630b05e5e032f5df417e4ebbba4e7","91c04d04e00a708cc9d97253899a1d4c40185d7ce9a123e81573b7665345f9d1","96bfb5ee6388338ee42459a1807b9a625d9ecb412008d41f250544f9d8dd8db0","9beacd1136548aebfa7577ae9037e5b1fa5af9aa91583a8ea8972a17c7809c56","a2ad15116f2371aeedb16177472483efb28ec95f78240f1537e50fafad16351c","a2ccfc569db06c83e6307604c6c2afe869a2ef6447554ece87f880d991f5743c","a48b38a945819526df8f745814d1162ece71b1f9a8180baab0f297d4e0818a04","a5ca5d99bb288a6757c4739d4d5bc6f151881258cf4a65d20eca57fa59607050","aac469abfee4b9a519ec671a2608abe79c9960734b48c633c662a8a38a1cc46c","ab891be17ccf138340fc211b010eda69b793ed201e5e209897167cd71e83d903","b15b881921e456efb84f37b0c8a07a0fa59e39411dc8cc065c4d9b3390ff06e8","b68fc38482559802f56e28388bd28e0070f321cde14589acac621e07d8906a78","b80d4143394be9a3ef40133184b2c573ad4c9aab89c5bd33884a8dace01025bf","bd83aadc47f618b3dca9efe2582d50b6e4dea820a77eafb36a1a5cd10c5615f4","c0622c68a321d3fa7bdfe5311aa2f202466b03678b337adc854f30f316c69b0d","c11934e52b3f321df01d871850754f055b229a61db6cf49858bea8b975647a3d","c77f88c2b764cf8ecd892dc5aa559fe940c8c90849e7c6bb8279463e516feaa8","cd243cbb6e93ed061c3476e193f2a05fb9223c101f144278febf8a54dc6eb2cb","cefb0b737d7547b81a571348f8de9574afb1febcd8e38e6c7146455342f20f40","cefc03cbc52f40d0ff34df5a6f403559ff0538322459be0aa39ae8ad7d65ae0e","d81a2c1a28992486c31a1a0a9221b1eb4313ad131b36fd25fc1be88b3016ff08","f0c55ed006d7ab28eb434671a3f9db8a8cdd77e66f42fafe1912ce4f1e2a30f0"],"recordQualifiers":{},"scopeLabel":"OMIM:211530","sourceIds":["OMIM:211530"],"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:0024537/OMIM:211530"],"expandColumnsLabel":"Compare all source entries","intro":"Compare the original source entries. Different entries may describe different patient groups.","primaryFeatureIds":[],"scopeNoteHtml":"

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.

"},"coverage":{"countRecords":19,"emptyColumnKeys":[],"hpoRelease":"2026-06-23","narrativeSourceChanges":[],"records":42,"sourceGroups":{"omim":20,"orphanet":0,"published":22}},"features":[{"hpoId":"HP:0001317","label":"Abnormal cerebellum morphology","primary":false},{"hpoId":"HP:0011448","label":"Ankle clonus","primary":false},{"hpoId":"HP:0001251","label":"Ataxia (coordination difficulty)","primary":false},{"hpoId":"HP:0001348","label":"Brisk reflexes","primary":false},{"hpoId":"HP:0001283","label":"Bulbar palsy","primary":false},{"hpoId":"HP:0002312","label":"Clumsiness","primary":false},{"hpoId":"HP:0007097","label":"Cranial nerve motor loss","primary":false},{"hpoId":"HP:0006824","label":"Cranial nerve paralysis","primary":false},{"hpoId":"HP:0009113","label":"Diaphragmatic weakness","primary":false},{"hpoId":"HP:0002015","label":"Dysphagia","primary":false},{"hpoId":"HP:0002094","label":"Dyspnea","primary":false},{"hpoId":"HP:0001298","label":"Encephalopathy","primary":false},{"hpoId":"HP:0000544","label":"External ophthalmoplegia","primary":false},{"hpoId":"HP:0010628","label":"Facial palsy","primary":false},{"hpoId":"HP:0002141","label":"Gait imbalance","primary":false},{"hpoId":"HP:0003324","label":"Generalized muscle weakness","primary":false},{"hpoId":"HP:0009130","label":"Hand muscle atrophy","primary":false},{"hpoId":"HP:0000365","label":"Hearing loss","primary":false},{"hpoId":"HP:0001347","label":"Hyperreflexia","primary":false},{"hpoId":"HP:0001252","label":"Hypotonia","primary":false},{"hpoId":"HP:0011449","label":"Knee clonus","primary":false},{"hpoId":"HP:0002808","label":"Kyphosis","primary":false},{"hpoId":"HP:0001324","label":"Muscle weakness","primary":false},{"hpoId":"HP:0002058","label":"Myopathic facies","primary":false},{"hpoId":"HP:0000467","label":"Neck muscle weakness","primary":false},{"hpoId":"HP:0002877","label":"Nocturnal hypoventilation","primary":false},{"hpoId":"HP:0009830","label":"Peripheral neuropathy","primary":false},{"hpoId":"HP:0003701","label":"Proximal muscle weakness","primary":false},{"hpoId":"HP:0000508","label":"Ptosis","primary":false},{"hpoId":"HP:0002205","label":"Recurrent respiratory infections","primary":false},{"hpoId":"HP:0002098","label":"Respiratory distress","primary":false},{"hpoId":"HP:0004887","label":"Respiratory failure requiring assisted ventilation","primary":false},{"hpoId":"HP:0002093","label":"Respiratory insufficiency","primary":false},{"hpoId":"HP:0002650","label":"Scoliosis","primary":false},{"hpoId":"HP:0000407","label":"Sensorineural hearing loss","primary":false},{"hpoId":"HP:0003202","label":"Skeletal muscle atrophy","primary":false},{"hpoId":"HP:0010307","label":"Stridor","primary":false},{"hpoId":"HP:0012473","label":"Tongue atrophy","primary":false},{"hpoId":"HP:0001308","label":"Tongue fasciculations","primary":false},{"hpoId":"HP:0002078","label":"Truncal ataxia","primary":false},{"hpoId":"HP:0001605","label":"Vocal cord paralysis","primary":false},{"hpoId":"HP:0001621","label":"Weak voice","primary":false}],"ledeHtml":"Riboflavin transporter deficiency neuronopathy is a disorder that affects nerve cells (neurons). Affected individuals typically have hearing loss caused by nerve damage in the inner ear (sensorineural hearing loss) and signs of damage to other nerves.","mondoId":"MONDO:0024537","records":[{"frequencyKind":"reported","key":"003005fcd51bf0659ad3de56b05c2e96a4ab821fc2d8c32f4b6b3375ff992ad8","raw":{"aspect":"P","body_system":"musculoskeletal","disease_id":"OMIM:211530","disease_name":"Brown-Vialetto-Van Laere syndrome 1","evidence":"IEA","frequency_raw":null,"hpo_id":"HP:0009113","is_excluded":false,"label":"Diaphragmatic weakness","onset_id":null,"reference":"OMIM:211530","source_release":"2026-06-23"},"sourceGroups":["omim"]},{"frequencyKind":"reported","key":"0c7eeaed4ed9aeafa016bfc57811f199dee670dd44771c3e88bdd672e9cd33c7","raw":{"aspect":"P","body_system":"nervous_system","disease_id":"OMIM:211530","disease_name":"Brown-Vialetto-Van Laere syndrome 1","evidence":"IEA","frequency_raw":null,"hpo_id":"HP:0011449","is_excluded":false,"label":"Knee clonus","onset_id":null,"reference":"OMIM:211530","source_release":"2026-06-23"},"sourceGroups":["omim"]},{"frequencyKind":"reported","key":"20517a1d10c0927094dc0b3637b0a75de413dc0cfb91a5efe8575ba0f841be31","raw":{"aspect":"P","body_system":"head_and_neck","disease_id":"OMIM:211530","disease_name":"Brown-Vialetto-Van Laere syndrome 1","evidence":"IEA","frequency_raw":null,"hpo_id":"HP:0001621","is_excluded":false,"label":"Weak voice","onset_id":null,"reference":"OMIM:211530","source_release":"2026-06-23"},"sourceGroups":["omim"]},{"frequencyKind":"count","key":"24d0ee57ce02a2a182e5d087ca815cd2b9946d0734ec21925831044ccaf55878","raw":{"aspect":"P","body_system":"respiratory","disease_id":"OMIM:211530","disease_name":"Brown-Vialetto-Van Laere syndrome 1","evidence":"PCS","frequency_raw":"1/9","hpo_id":"HP:0004887","is_excluded":false,"label":"Respiratory failure requiring assisted ventilation","onset_id":null,"reference":"PMID:20206331","source_release":"2026-06-23"},"sourceGroups":["published"]},{"frequencyKind":"reported","key":"289ebac9a5d402a639bc64302e50d5e6fe4b80aa6bb7db938b8094ef1b486ba3","raw":{"aspect":"P","body_system":"nervous_system","disease_id":"OMIM:211530","disease_name":"Brown-Vialetto-Van Laere syndrome 1","evidence":"IEA","frequency_raw":null,"hpo_id":"HP:0001317","is_excluded":false,"label":"Abnormal cerebellum morphology","onset_id":null,"reference":"OMIM:211530","source_release":"2026-06-23"},"sourceGroups":["omim"]},{"frequencyKind":"count","key":"2cba9c30448f717be3dcbe654bf6d2c58857ef94a1507e436e946eeef1a32d25","raw":{"aspect":"P","body_system":"musculoskeletal","disease_id":"OMIM:211530","disease_name":"Brown-Vialetto-Van Laere syndrome 1","evidence":"PCS","frequency_raw":"2/9","hpo_id":"HP:0001252","is_excluded":false,"label":"Hypotonia","onset_id":null,"reference":"PMID:20206331","source_release":"2026-06-23"},"sourceGroups":["published"]},{"frequencyKind":"count","key":"36d18a678bd094994099003c36a261c3b29c3de47cfa08db268476a40f2a6b0e","raw":{"aspect":"P","body_system":"nervous_system","disease_id":"OMIM:211530","disease_name":"Brown-Vialetto-Van Laere syndrome 1","evidence":"PCS","frequency_raw":"1/9","hpo_id":"HP:0001298","is_excluded":false,"label":"Encephalopathy","onset_id":null,"reference":"PMID:20206331","source_release":"2026-06-23"},"sourceGroups":["published"]},{"frequencyKind":"count","key":"3883469dc97f3880b40248f979c102729b3ed3a767396930f41ea6beaa0973f1","raw":{"aspect":"P","body_system":"ear","disease_id":"OMIM:211530","disease_name":"Brown-Vialetto-Van Laere syndrome 1","evidence":"PCS","frequency_raw":"2/9","hpo_id":"HP:0000365","is_excluded":false,"label":"Hearing impairment","onset_id":null,"reference":"PMID:20206331","source_release":"2026-06-23"},"sourceGroups":["published"]},{"frequencyKind":"reported","key":"442b08fc26fb548e5f18397f8c9e7bcf9f9db4a529fd9e0e11e9bb754f24d1d1","raw":{"aspect":"P","body_system":"respiratory","disease_id":"OMIM:211530","disease_name":"Brown-Vialetto-Van Laere syndrome 1","evidence":"PCS","frequency_raw":null,"hpo_id":"HP:0002098","is_excluded":false,"label":"Respiratory distress","onset_id":null,"reference":"PMID:20206331","source_release":"2026-06-23"},"sourceGroups":["published"]},{"frequencyKind":"count","key":"4d03a58f87da9cf21a917d93ddbf9266f1ea78723720374a39f976f884b894f4","raw":{"aspect":"P","body_system":"musculoskeletal","disease_id":"OMIM:211530","disease_name":"Brown-Vialetto-Van Laere syndrome 1","evidence":"PCS","frequency_raw":"1/9","hpo_id":"HP:0003324","is_excluded":false,"label":"Generalized muscle weakness","onset_id":null,"reference":"PMID:20206331","source_release":"2026-06-23"},"sourceGroups":["published"]},{"frequencyKind":"range","key":"54ebc4b6a853dc6f04dfd910f0cceab53a0b2a68040537d94b6f51d0dfd6a4e6","raw":{"aspect":"P","body_system":"nervous_system","disease_id":"OMIM:211530","disease_name":"Brown-Vialetto-Van Laere syndrome 1","evidence":"IEA","frequency_raw":"HP:0040283","hpo_id":"HP:0001251","is_excluded":false,"label":"Ataxia","onset_id":null,"reference":"OMIM:211530","source_release":"2026-06-23"},"sourceGroups":["omim"]},{"frequencyKind":"reported","key":"5bb31a9b1cc8a695df15cfb9ddf7945ef17f5a5defa9e9d9d8b3b783ed595e88","raw":{"aspect":"P","body_system":"nervous_system","disease_id":"OMIM:211530","disease_name":"Brown-Vialetto-Van Laere syndrome 1","evidence":"IEA","frequency_raw":null,"hpo_id":"HP:0002312","is_excluded":false,"label":"Clumsiness","onset_id":null,"reference":"OMIM:211530","source_release":"2026-06-23"},"sourceGroups":["omim"]},{"frequencyKind":"count","key":"5fe53858587b2513cbbdb309e535f61e96de324a4487df9e49c1f400348c7ebc","raw":{"aspect":"P","body_system":"respiratory","disease_id":"OMIM:211530","disease_name":"Brown-Vialetto-Van Laere syndrome 1","evidence":"PCS","frequency_raw":"3/9","hpo_id":"HP:0010307","is_excluded":false,"label":"Stridor","onset_id":null,"reference":"PMID:20206331","source_release":"2026-06-23"},"sourceGroups":["published"]},{"frequencyKind":"reported","key":"60c07a3418482a3be0f293ac25cb31a38794834f50a075a0cd79b98e38c584e7","raw":{"aspect":"P","body_system":"respiratory","disease_id":"OMIM:211530","disease_name":"Brown-Vialetto-Van Laere syndrome 1","evidence":"IEA","frequency_raw":null,"hpo_id":"HP:0002877","is_excluded":false,"label":"Nocturnal hypoventilation","onset_id":null,"reference":"OMIM:211530","source_release":"2026-06-23"},"sourceGroups":["omim"]},{"frequencyKind":"reported","key":"683e08b2b374758eaca06be7dfa7db45611a18031492bdd7c3915fca6a5110fd","raw":{"aspect":"P","body_system":"nervous_system","disease_id":"OMIM:211530","disease_name":"Brown-Vialetto-Van Laere syndrome 1","evidence":"IEA","frequency_raw":null,"hpo_id":"HP:0001347","is_excluded":false,"label":"Hyperreflexia","onset_id":null,"reference":"OMIM:211530","source_release":"2026-06-23"},"sourceGroups":["omim"]},{"frequencyKind":"count","key":"6dfd73a92f7040fe77a3cf475e6052cce5710a4bad282fb65918bd3f5615ef21","raw":{"aspect":"P","body_system":"nervous_system","disease_id":"OMIM:211530","disease_name":"Brown-Vialetto-Van Laere syndrome 1","evidence":"PCS","frequency_raw":"2/9","hpo_id":"HP:0001308","is_excluded":false,"label":"Tongue fasciculations","onset_id":null,"reference":"PMID:20206331","source_release":"2026-06-23"},"sourceGroups":["published"]},{"frequencyKind":"count","key":"7baf5ffc4866a3a93662594c1f82ea689b55ab542baab66a57d90a2c241224a4","raw":{"aspect":"P","body_system":"eye","disease_id":"OMIM:211530","disease_name":"Brown-Vialetto-Van Laere syndrome 1","evidence":"PCS","frequency_raw":"1/9","hpo_id":"HP:0000544","is_excluded":false,"label":"External ophthalmoplegia","onset_id":null,"reference":"PMID:20206331","source_release":"2026-06-23"},"sourceGroups":["published"]},{"frequencyKind":"reported","key":"7e24af744274ea63f5d0635319daf29ef10246d6a7cf553866274ca39f64007b","raw":{"aspect":"P","body_system":"head_and_neck","disease_id":"OMIM:211530","disease_name":"Brown-Vialetto-Van Laere syndrome 1","evidence":"IEA","frequency_raw":null,"hpo_id":"HP:0001605","is_excluded":false,"label":"Vocal cord paralysis","onset_id":null,"reference":"OMIM:211530","source_release":"2026-06-23"},"sourceGroups":["omim"]},{"frequencyKind":"reported","key":"807c0f406a515b138138062ae34c5a7110daed8cb4c536f63d2e7139d25633b9","raw":{"aspect":"P","body_system":"ear","disease_id":"OMIM:211530","disease_name":"Brown-Vialetto-Van Laere syndrome 1","evidence":"PCS","frequency_raw":null,"hpo_id":"HP:0000407","is_excluded":false,"label":"Sensorineural hearing impairment","onset_id":null,"reference":"PMID:20206331","source_release":"2026-06-23"},"sourceGroups":["published"]},{"frequencyKind":"count","key":"81ad2163e05e7dfd2179e1f6e303069c2969561626646e4b429c52924e884132","raw":{"aspect":"P","body_system":"nervous_system","disease_id":"OMIM:211530","disease_name":"Brown-Vialetto-Van Laere syndrome 1","evidence":"PCS","frequency_raw":"1/9","hpo_id":"HP:0001348","is_excluded":false,"label":"Brisk reflexes","onset_id":null,"reference":"PMID:20206331","source_release":"2026-06-23"},"sourceGroups":["published"]},{"frequencyKind":"count","key":"847e146c40012c7b4ac8b110866190ba271630b05e5e032f5df417e4ebbba4e7","raw":{"aspect":"P","body_system":"musculoskeletal","disease_id":"OMIM:211530","disease_name":"Brown-Vialetto-Van Laere syndrome 1","evidence":"PCS","frequency_raw":"2/9","hpo_id":"HP:0003202","is_excluded":false,"label":"Skeletal muscle atrophy","onset_id":null,"reference":"PMID:20206331","source_release":"2026-06-23"},"sourceGroups":["published"]},{"frequencyKind":"count","key":"91c04d04e00a708cc9d97253899a1d4c40185d7ce9a123e81573b7665345f9d1","raw":{"aspect":"P","body_system":"nervous_system","disease_id":"OMIM:211530","disease_name":"Brown-Vialetto-Van Laere syndrome 1","evidence":"PCS","frequency_raw":"1/9","hpo_id":"HP:0002078","is_excluded":false,"label":"Truncal ataxia","onset_id":null,"reference":"PMID:20206331","source_release":"2026-06-23"},"sourceGroups":["published"]},{"frequencyKind":"reported","key":"96bfb5ee6388338ee42459a1807b9a625d9ecb412008d41f250544f9d8dd8db0","raw":{"aspect":"P","body_system":"nervous_system","disease_id":"OMIM:211530","disease_name":"Brown-Vialetto-Van Laere syndrome 1","evidence":"IEA","frequency_raw":null,"hpo_id":"HP:0007097","is_excluded":false,"label":"Cranial nerve motor loss","onset_id":null,"reference":"OMIM:211530","source_release":"2026-06-23"},"sourceGroups":["omim"]},{"frequencyKind":"reported","key":"9beacd1136548aebfa7577ae9037e5b1fa5af9aa91583a8ea8972a17c7809c56","raw":{"aspect":"P","body_system":"musculoskeletal","disease_id":"OMIM:211530","disease_name":"Brown-Vialetto-Van Laere syndrome 1","evidence":"IEA","frequency_raw":null,"hpo_id":"HP:0009130","is_excluded":false,"label":"Hand muscle atrophy","onset_id":null,"reference":"OMIM:211530","source_release":"2026-06-23"},"sourceGroups":["omim"]},{"frequencyKind":"reported","key":"a2ad15116f2371aeedb16177472483efb28ec95f78240f1537e50fafad16351c","raw":{"aspect":"P","body_system":"nervous_system","disease_id":"OMIM:211530","disease_name":"Brown-Vialetto-Van Laere syndrome 1","evidence":"IEA","frequency_raw":null,"hpo_id":"HP:0002015","is_excluded":false,"label":"Dysphagia","onset_id":null,"reference":"OMIM:211530","source_release":"2026-06-23"},"sourceGroups":["omim"]},{"frequencyKind":"reported","key":"a2ccfc569db06c83e6307604c6c2afe869a2ef6447554ece87f880d991f5743c","raw":{"aspect":"P","body_system":"respiratory","disease_id":"OMIM:211530","disease_name":"Brown-Vialetto-Van Laere syndrome 1","evidence":"TAS","frequency_raw":null,"hpo_id":"HP:0002094","is_excluded":false,"label":"Dyspnea","onset_id":null,"reference":"OMIM:211530","source_release":"2026-06-23"},"sourceGroups":["omim"]},{"frequencyKind":"count","key":"a48b38a945819526df8f745814d1162ece71b1f9a8180baab0f297d4e0818a04","raw":{"aspect":"P","body_system":"nervous_system","disease_id":"OMIM:211530","disease_name":"Brown-Vialetto-Van Laere syndrome 1","evidence":"PCS","frequency_raw":"2/9","hpo_id":"HP:0010628","is_excluded":false,"label":"Facial palsy","onset_id":null,"reference":"PMID:20206331","source_release":"2026-06-23"},"sourceGroups":["published"]},{"frequencyKind":"reported","key":"a5ca5d99bb288a6757c4739d4d5bc6f151881258cf4a65d20eca57fa59607050","raw":{"aspect":"P","body_system":"eye","disease_id":"OMIM:211530","disease_name":"Brown-Vialetto-Van Laere syndrome 1","evidence":"IEA","frequency_raw":null,"hpo_id":"HP:0000508","is_excluded":false,"label":"Ptosis","onset_id":null,"reference":"OMIM:211530","source_release":"2026-06-23"},"sourceGroups":["omim"]},{"frequencyKind":"count","key":"aac469abfee4b9a519ec671a2608abe79c9960734b48c633c662a8a38a1cc46c","raw":{"aspect":"P","body_system":"nervous_system","disease_id":"OMIM:211530","disease_name":"Brown-Vialetto-Van Laere syndrome 1","evidence":"PCS","frequency_raw":"1/9","hpo_id":"HP:0011448","is_excluded":false,"label":"Ankle clonus","onset_id":null,"reference":"PMID:20206331","source_release":"2026-06-23"},"sourceGroups":["published"]},{"frequencyKind":"count","key":"ab891be17ccf138340fc211b010eda69b793ed201e5e209897167cd71e83d903","raw":{"aspect":"P","body_system":"nervous_system","disease_id":"OMIM:211530","disease_name":"Brown-Vialetto-Van Laere syndrome 1","evidence":"PCS","frequency_raw":"1/9","hpo_id":"HP:0009830","is_excluded":false,"label":"Peripheral neuropathy","onset_id":null,"reference":"PMID:20206331","source_release":"2026-06-23"},"sourceGroups":["published"]},{"frequencyKind":"reported","key":"b15b881921e456efb84f37b0c8a07a0fa59e39411dc8cc065c4d9b3390ff06e8","raw":{"aspect":"P","body_system":"head_and_neck","disease_id":"OMIM:211530","disease_name":"Brown-Vialetto-Van Laere syndrome 1","evidence":"IEA","frequency_raw":null,"hpo_id":"HP:0002058","is_excluded":false,"label":"Myopathic facies","onset_id":null,"reference":"OMIM:211530","source_release":"2026-06-23"},"sourceGroups":["omim"]},{"frequencyKind":"count","key":"b68fc38482559802f56e28388bd28e0070f321cde14589acac621e07d8906a78","raw":{"aspect":"P","body_system":"head_and_neck","disease_id":"OMIM:211530","disease_name":"Brown-Vialetto-Van Laere syndrome 1","evidence":"PCS","frequency_raw":"1/9","hpo_id":"HP:0012473","is_excluded":false,"label":"Tongue atrophy","onset_id":null,"reference":"PMID:20206331","source_release":"2026-06-23"},"sourceGroups":["published"]},{"frequencyKind":"reported","key":"b80d4143394be9a3ef40133184b2c573ad4c9aab89c5bd33884a8dace01025bf","raw":{"aspect":"P","body_system":"musculoskeletal","disease_id":"OMIM:211530","disease_name":"Brown-Vialetto-Van Laere syndrome 1","evidence":"IEA","frequency_raw":null,"hpo_id":"HP:0002650","is_excluded":false,"label":"Scoliosis","onset_id":null,"reference":"OMIM:211530","source_release":"2026-06-23"},"sourceGroups":["omim"]},{"frequencyKind":"reported","key":"bd83aadc47f618b3dca9efe2582d50b6e4dea820a77eafb36a1a5cd10c5615f4","raw":{"aspect":"P","body_system":"nervous_system","disease_id":"OMIM:211530","disease_name":"Brown-Vialetto-Van Laere syndrome 1","evidence":"TAS","frequency_raw":null,"hpo_id":"HP:0006824","is_excluded":false,"label":"Cranial nerve paralysis","onset_id":null,"reference":"OMIM:211530","source_release":"2026-06-23"},"sourceGroups":["omim"]},{"frequencyKind":"reported","key":"c0622c68a321d3fa7bdfe5311aa2f202466b03678b337adc854f30f316c69b0d","raw":{"aspect":"P","body_system":"respiratory","disease_id":"OMIM:211530","disease_name":"Brown-Vialetto-Van Laere syndrome 1","evidence":"IEA","frequency_raw":null,"hpo_id":"HP:0002205","is_excluded":false,"label":"Recurrent respiratory infections","onset_id":null,"reference":"OMIM:211530","source_release":"2026-06-23"},"sourceGroups":["omim"]},{"frequencyKind":"reported","key":"c11934e52b3f321df01d871850754f055b229a61db6cf49858bea8b975647a3d","raw":{"aspect":"P","body_system":"musculoskeletal","disease_id":"OMIM:211530","disease_name":"Brown-Vialetto-Van Laere syndrome 1","evidence":"IEA","frequency_raw":null,"hpo_id":"HP:0002808","is_excluded":false,"label":"Kyphosis","onset_id":null,"reference":"OMIM:211530","source_release":"2026-06-23"},"sourceGroups":["omim"]},{"frequencyKind":"reported","key":"c77f88c2b764cf8ecd892dc5aa559fe940c8c90849e7c6bb8279463e516feaa8","raw":{"aspect":"P","body_system":"respiratory","disease_id":"OMIM:211530","disease_name":"Brown-Vialetto-Van Laere syndrome 1","evidence":"PCS","frequency_raw":null,"hpo_id":"HP:0002093","is_excluded":false,"label":"Respiratory insufficiency","onset_id":null,"reference":"PMID:20206331","source_release":"2026-06-23"},"sourceGroups":["published"]},{"frequencyKind":"count","key":"cd243cbb6e93ed061c3476e193f2a05fb9223c101f144278febf8a54dc6eb2cb","raw":{"aspect":"P","body_system":"nervous_system","disease_id":"OMIM:211530","disease_name":"Brown-Vialetto-Van Laere syndrome 1","evidence":"PCS","frequency_raw":"1/9","hpo_id":"HP:0002141","is_excluded":false,"label":"Gait imbalance","onset_id":null,"reference":"PMID:20206331","source_release":"2026-06-23"},"sourceGroups":["published"]},{"frequencyKind":"count","key":"cefb0b737d7547b81a571348f8de9574afb1febcd8e38e6c7146455342f20f40","raw":{"aspect":"P","body_system":"nervous_system","disease_id":"OMIM:211530","disease_name":"Brown-Vialetto-Van Laere syndrome 1","evidence":"PCS","frequency_raw":"3/9","hpo_id":"HP:0001283","is_excluded":false,"label":"Bulbar palsy","onset_id":null,"reference":"PMID:20206331","source_release":"2026-06-23"},"sourceGroups":["published"]},{"frequencyKind":"count","key":"cefc03cbc52f40d0ff34df5a6f403559ff0538322459be0aa39ae8ad7d65ae0e","raw":{"aspect":"P","body_system":"musculoskeletal","disease_id":"OMIM:211530","disease_name":"Brown-Vialetto-Van Laere syndrome 1","evidence":"PCS","frequency_raw":"3/9","hpo_id":"HP:0001324","is_excluded":false,"label":"Muscle weakness","onset_id":null,"reference":"PMID:20206331","source_release":"2026-06-23"},"sourceGroups":["published"]},{"frequencyKind":"count","key":"d81a2c1a28992486c31a1a0a9221b1eb4313ad131b36fd25fc1be88b3016ff08","raw":{"aspect":"P","body_system":"musculoskeletal","disease_id":"OMIM:211530","disease_name":"Brown-Vialetto-Van Laere syndrome 1","evidence":"PCS","frequency_raw":"1/9","hpo_id":"HP:0003701","is_excluded":false,"label":"Proximal muscle weakness","onset_id":null,"reference":"PMID:20206331","source_release":"2026-06-23"},"sourceGroups":["published"]},{"frequencyKind":"reported","key":"f0c55ed006d7ab28eb434671a3f9db8a8cdd77e66f42fafe1912ce4f1e2a30f0","raw":{"aspect":"P","body_system":"musculoskeletal","disease_id":"OMIM:211530","disease_name":"Brown-Vialetto-Van Laere syndrome 1","evidence":"IEA","frequency_raw":null,"hpo_id":"HP:0000467","is_excluded":false,"label":"Neck muscle weakness","onset_id":null,"reference":"OMIM:211530","source_release":"2026-06-23"},"sourceGroups":["omim"]}],"referenceLabels":{},"references":{"causeHtml":"","identityNote":"MONDO cross-references identify native condition entries. Ancestor membership does not transfer phenotype values between groups.","importantHtml":""},"sections":[{"bodyHtml":"

Riboflavin transporter deficiency neuronopathy is caused by mutations in the SLC52A2 or SLC52A3 gene. These genes provide instructions for making related proteins called riboflavin transporters: RFVT2 is produced from the SLC52A2 gene, and RFVT3 is produced from the SLC52A3 gene. Both proteins move (transport) a vitamin called riboflavin (also called vitamin B2) across the cell membrane. Riboflavin cannot be made by the body, so it must be obtained from the food a person eats. The RFVT3 protein is found at especially high levels in cells of the small intestine and is important for absorbing riboflavin during digestion so that the vitamin can be used in the body. The RFVT2 protein is found in cells of the brain and spinal cord and is important for ensuring that these tissues have enough riboflavin for proper functioning.

In the cells of the body, riboflavin is the core component of molecules called flavin adenine dinucleotide (FAD) and flavin mononucleotide (FMN). FAD and FMN are involved in many different chemical reactions and are required for a variety of cellular processes. One important role of these molecules is in the production of energy for cells. FAD and FMN are also involved in the breakdown (metabolism) of carbohydrates, fats, and proteins.

Mutations in the SLC52A2 or SLC52A3 gene lead to an abnormal riboflavin transporter protein with impaired ability to transport riboflavin. Consequently, there is a reduction of riboflavin available in the body. However, it is unclear how these changes lead to the nerve problems characteristic of riboflavin transporter deficiency neuronopathy.

MedlinePlus Genetics: Causes

","key":"forms","title":"What causes Riboflavin transporter deficiency neuronopathy?"},{"bodyHtml":"

In addition to nerves in the inner ear, riboflavin transporter deficiency neuronopathy involves nerves found in the part of the brain that is connected to the spinal cord (the brainstem), specifically in a region of the brainstem known as the pontobulbar region. Damage to these nerves causes paralysis of the muscles controlled by them, a condition called pontobulbar palsy. Nerves in the pontobulbar region help control several voluntary muscle activities, including breathing, speaking, and moving the limbs. As a result of pontobulbar palsy, people with riboflavin transporter deficiency neuronopathy can have breathing problems; slurred speech; and muscle weakness in the face, neck, shoulders, and limbs. Affected individuals can also have muscle stiffness (spasticity) and exaggerated reflexes.

The age at which riboflavin transporter deficiency neuronopathy begins varies from infancy to young adulthood. When the condition begins in infancy, the first symptom is often breathing problems caused by nerve damage, which can be life-threatening. When the condition begins in children or young adults, sensorineural hearing loss usually occurs first, followed by signs of pontobulbar palsy.

If not treated, the signs and symptoms of riboflavin transporter deficiency neuronopathy worsen over time. Severe breathing problems and respiratory infections are the usual cause of death in people with this condition. Without treatment, affected infants typically survive less than one year. However, those who develop the condition after age 4 often survive more than 10 years.

Riboflavin transporter deficiency neuronopathy encompasses two conditions that were once considered distinct disorders: Brown-Vialetto-Van Laere syndrome (BVVLS) and Fazio-Londe disease. The two conditions have similar signs and symptoms, but Fazio-Londe disease does not include sensorineural hearing loss. Because these two conditions share a genetic cause and have overlapping features, researchers determined that they are forms of a single disorder.

Source: MedlinePlus Genetics

","key":"overview","title":"Condition overview"}],"sharedSources":[],"slug":"riboflavin-transporter-deficiency-neuronopathy","sourceDocuments":[{"name":"Riboflavin transporter deficiency neuronopathy","reviewed":"2016-01","sections":{"causes":{"fetchedAt":"2026-10-20T20:24:45.509820+00:00","label":"Causes","pageSha256":"acf1aed6ff52e2ac1b9683ceee43bcb628c385875812778cb16b06652b804a42","sourceUrl":"https://medlineplus.gov/genetics/condition/riboflavin-transporter-deficiency-neuronopathy/#causes","status":"available"}},"source_release":"2026-10-01","url":"https://medlineplus.gov/genetics/condition/riboflavin-transporter-deficiency-neuronopathy"}],"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":"Riboflavin transporter deficiency neuronopathy"},"schemaVersion":1}