{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,23]],"date-time":"2026-09-23T16:15:56Z","timestamp":1790180156350,"version":"4.1.0"},"reference-count":27,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2021,11,10]],"date-time":"2021-11-10T00:00:00Z","timestamp":1636502400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Cells"],"abstract":"<jats:p>Congenital disorders of glycosylation (CDG), inherited metabolic diseases caused by defects in glycosylation, are characterized by a high frequency of intellectual disability (ID) and various clinical manifestations. Two siblings with ID, dysmorphic features, and epilepsy were examined using mass spectrometry of serum transferrin, which revealed a CDG type 2 pattern. Whole-exome sequencing showed that both patients were homozygous for a novel pathogenic variant of MAN1B1 (NM_016219.4:c.1837del) inherited from their healthy parents. We conducted a HPLC analysis of sialylated N-linked glycans released from total plasma proteins and characterized the \u03b11,2-mannosidase I activity of the lymphocyte microsome fraction. The accumulation of monosialoglycans was observed in MAN1B1-deficient patients, indicating N-glycan-processing defects. The enzymatic activity of MAN1B1 was compromised in patient-derived lymphocytes. The present patients exhibited unique manifestations including early-onset epileptic encephalopathy and cerebral infarction. They also showed coagulation abnormalities and hypertransaminasemia. Neither sibling had truncal obesity, which is one of the characteristic features of MAN1B1-CDG.<\/jats:p>","DOI":"10.3390\/cells10113117","type":"journal-article","created":{"date-parts":[[2021,11,11]],"date-time":"2021-11-11T23:02:41Z","timestamp":1636671761000},"page":"3117","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":14,"title":["Siblings with MAN1B1-CDG Showing Novel Biochemical Profiles"],"prefix":"10.3390","volume":"10","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-5415-656X","authenticated-orcid":false,"given":"Nobuhiko","family":"Okamoto","sequence":"first","affiliation":[{"name":"Department of Medical Genetics, Osaka Women\u2019s and Children\u2019s Hospital, Izumi 594-1101, Japan"},{"name":"Department of Molecular Medicine, Research Institute, Osaka Women\u2019s and Children\u2019s Hospital, Izumi 594-1101, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5321-8869","authenticated-orcid":false,"given":"Tatsuyuki","family":"Ohto","sequence":"additional","affiliation":[{"name":"Department of Pediatrics, Tsukuba University Faculty of Medicine, Tsukuba 305-8576, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6377-997X","authenticated-orcid":false,"given":"Takashi","family":"Enokizono","sequence":"additional","affiliation":[{"name":"Department of Pediatrics, Tsukuba University Faculty of Medicine, Tsukuba 305-8576, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yoshinao","family":"Wada","sequence":"additional","affiliation":[{"name":"Department of Molecular Medicine, Research Institute, Osaka Women\u2019s and Children\u2019s Hospital, Izumi 594-1101, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tomohiro","family":"Kohmoto","sequence":"additional","affiliation":[{"name":"Division of Molecular Genetics, Aichi Cancer Center Research Institute, Nagoya 464-8681, Japan"},{"name":"Department of Human Genetics, Graduate School of Biomedical Science, Tokushima University Graduate School, Tokushima 770-8503, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Issei","family":"Imoto","sequence":"additional","affiliation":[{"name":"Division of Molecular Genetics, Aichi Cancer Center Research Institute, Nagoya 464-8681, Japan"},{"name":"Department of Human Genetics, Graduate School of Biomedical Science, Tokushima University Graduate School, Tokushima 770-8503, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7861-617X","authenticated-orcid":false,"given":"Yoshimi","family":"Haga","sequence":"additional","affiliation":[{"name":"Glycometabolic Biochemistry Laboratory, RIKEN Cluster for Pioneering Research (CPR), 2-1 Hirosawa, Wako 351-0198, Japan"},{"name":"Cancer Proteomics Group, Cancer Precision Medicine Center, Japanese Foundation for Cancer Research, 3-8-31 Ariake, Koto-ku, Tokyo 135-8550, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Junichi","family":"Seino","sequence":"additional","affiliation":[{"name":"Glycometabolic Biochemistry Laboratory, RIKEN Cluster for Pioneering Research (CPR), 2-1 Hirosawa, Wako 351-0198, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tadashi","family":"Suzuki","sequence":"additional","affiliation":[{"name":"Glycometabolic Biochemistry Laboratory, RIKEN Cluster for Pioneering Research (CPR), 2-1 Hirosawa, Wako 351-0198, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,11,10]]},"reference":[{"key":"ref_1","first-page":"14","article-title":"Congenital disorders of glycosylation: A multi-genetic disease family with multiple subcellular locations","volume":"24","author":"Jaeken","year":"2020","journal-title":"J. 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