Maternal Primary Carnitine Deficiency and a Novel Solute Carrier Family 22 Member 5 (SLC22A5) Mutation
Primary carnitine deficiency (PCD) is a rare autosomal recessive disorder caused by loss of function mutations in the solute carrier family 22 member 5 ( SLC22A5 ) gene that encodes a high-affinity sodium-ion–dependent organic cation transporter protein (OCTN2). Reduced carnitine transport results i...
| Main Authors: | , , , |
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| Format: | Article |
| Language: | English |
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SAGE Publishing
2021-05-01
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| Series: | Journal of Investigative Medicine High Impact Case Reports |
| Online Access: | https://doi.org/10.1177/23247096211019543 |
| _version_ | 1819094077076930560 |
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| author | Michael Jakoby MD, MA Amruta Jaju MD Aundrea Marsh BS Andrew Wilber PhD |
| author_facet | Michael Jakoby MD, MA Amruta Jaju MD Aundrea Marsh BS Andrew Wilber PhD |
| author_sort | Michael Jakoby MD, MA |
| collection | DOAJ |
| description | Primary carnitine deficiency (PCD) is a rare autosomal recessive disorder caused by loss of function mutations in the solute carrier family 22 member 5 ( SLC22A5 ) gene that encodes a high-affinity sodium-ion–dependent organic cation transporter protein (OCTN2). Reduced carnitine transport results in diminished fatty acid oxidation in heart and skeletal muscle and carnitine wasting in urine. We present a case of PCD diagnosed in an adult female after a positive newborn screen (NBS) for PCD that was not confirmed on follow-up testing. The mother was referred for evaluation of persistent fatigue and possible hypothyroidism even though all measurements of thyroid-stimulating hormone were well within the range of 0.4 to 2.5 mIU/L expected for reproductive-age women. She was found to have unequivocally low levels of both total carnitine and carnitine esters, and genetic testing revealed compound heterozygosity for 2 SLC22A5 mutations. One mutation (c.34G>A [p.Gly12Ser]) is a known missense mutation with partial OCTN2 activity, but the other mutation (c.41G>A [p.Trp14Ter]) is previously unreported and results in a premature stop codon and truncated OCTN2. This case illustrates that some maternal inborn errors of metabolism can be identified by NBS and that maternal carnitine levels should be checked after a positive NBS test for PCD. |
| first_indexed | 2024-12-21T23:21:40Z |
| format | Article |
| id | doaj.art-391c8bfa792e4ca4a4f1308d97341c65 |
| institution | Directory Open Access Journal |
| issn | 2324-7096 |
| language | English |
| last_indexed | 2024-12-21T23:21:40Z |
| publishDate | 2021-05-01 |
| publisher | SAGE Publishing |
| record_format | Article |
| series | Journal of Investigative Medicine High Impact Case Reports |
| spelling | doaj.art-391c8bfa792e4ca4a4f1308d97341c652022-12-21T18:46:46ZengSAGE PublishingJournal of Investigative Medicine High Impact Case Reports2324-70962021-05-01910.1177/23247096211019543Maternal Primary Carnitine Deficiency and a Novel Solute Carrier Family 22 Member 5 (SLC22A5) MutationMichael Jakoby MD, MA0Amruta Jaju MD1Aundrea Marsh BS2Andrew Wilber PhD3Southern Illinois University, Springfield, IL, USASouthern Illinois University, Springfield, IL, USASouthern Illinois University, Springfield, IL, USASouthern Illinois University, Springfield, IL, USAPrimary carnitine deficiency (PCD) is a rare autosomal recessive disorder caused by loss of function mutations in the solute carrier family 22 member 5 ( SLC22A5 ) gene that encodes a high-affinity sodium-ion–dependent organic cation transporter protein (OCTN2). Reduced carnitine transport results in diminished fatty acid oxidation in heart and skeletal muscle and carnitine wasting in urine. We present a case of PCD diagnosed in an adult female after a positive newborn screen (NBS) for PCD that was not confirmed on follow-up testing. The mother was referred for evaluation of persistent fatigue and possible hypothyroidism even though all measurements of thyroid-stimulating hormone were well within the range of 0.4 to 2.5 mIU/L expected for reproductive-age women. She was found to have unequivocally low levels of both total carnitine and carnitine esters, and genetic testing revealed compound heterozygosity for 2 SLC22A5 mutations. One mutation (c.34G>A [p.Gly12Ser]) is a known missense mutation with partial OCTN2 activity, but the other mutation (c.41G>A [p.Trp14Ter]) is previously unreported and results in a premature stop codon and truncated OCTN2. This case illustrates that some maternal inborn errors of metabolism can be identified by NBS and that maternal carnitine levels should be checked after a positive NBS test for PCD.https://doi.org/10.1177/23247096211019543 |
| spellingShingle | Michael Jakoby MD, MA Amruta Jaju MD Aundrea Marsh BS Andrew Wilber PhD Maternal Primary Carnitine Deficiency and a Novel Solute Carrier Family 22 Member 5 (SLC22A5) Mutation Journal of Investigative Medicine High Impact Case Reports |
| title | Maternal Primary Carnitine Deficiency and a Novel Solute Carrier Family 22 Member 5 (SLC22A5) Mutation |
| title_full | Maternal Primary Carnitine Deficiency and a Novel Solute Carrier Family 22 Member 5 (SLC22A5) Mutation |
| title_fullStr | Maternal Primary Carnitine Deficiency and a Novel Solute Carrier Family 22 Member 5 (SLC22A5) Mutation |
| title_full_unstemmed | Maternal Primary Carnitine Deficiency and a Novel Solute Carrier Family 22 Member 5 (SLC22A5) Mutation |
| title_short | Maternal Primary Carnitine Deficiency and a Novel Solute Carrier Family 22 Member 5 (SLC22A5) Mutation |
| title_sort | maternal primary carnitine deficiency and a novel solute carrier family 22 member 5 slc22a5 mutation |
| url | https://doi.org/10.1177/23247096211019543 |
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