TY - JOUR
T1 - Mosaicism of the UDP-Galactose transporter SLC35A2 in a female causing a congenital disorder of glycosylation
T2 - A case report
AU - Westenfield, Kristen
AU - Sarafoglou, Kyriakie M
AU - Speltz, Laura C
AU - Pierpont, Rene
AU - Steyermark, Joan
AU - Nascene, David R
AU - Bower, Matthew
AU - Pierpont, Mary Ella M
N1 - Publisher Copyright:
© 2018 The Author(s).
PY - 2018/6/15
Y1 - 2018/6/15
N2 - Background: Congenital disorders of glycosylation are rare conditions caused by genetic defects in glycan synthesis, processing or transport. Most congenital disorders of glycosylation involve defects in the formation or transfer of the lipid-linked oligosaccharide precursor of N-linked glycans. SLC35A2-CDG (previously CDG-IIm) is caused by hemizygous or heterozygous mutations in the X-linked gene SLC35A2 that encodes a UDP-galactose transporter. To date there have only been 10 reported patients with SLC35A2 mutations. Importantly, the patient presented here was not identified in infancy by transferrin isoform analysis, the most common testing to identify patients with a congenital disorder of glycosylation. Case presentation: A 27 month old girl with developmental delay, central hypotonia, cerebral atrophy, and failure to thrive with growth retardation was identified by whole exome sequencing to have a mosaic missense variant in SLC35A2 (c.991G > A). This particular variant has been previously reported in a male as a mutation. Comparison of all clinical findings and new information on growth pattern, growth hormone testing and neurodevelopmental evaluation are detailed on the patient presented. Conclusion: This patient report increases the clinical and scientific knowledge of SLC35A2-CDG, a rare condition. New information on reduced growth, growth hormone sufficiency, lack of seizures, and neurodevelopmental status are presented. This new information will be helpful to clinicians caring for individuals with SLC35A2-CDG. This report also alerts clinicians that transferrin isoform measurements do not identify all patients with congenital disorders of glycosylation.
AB - Background: Congenital disorders of glycosylation are rare conditions caused by genetic defects in glycan synthesis, processing or transport. Most congenital disorders of glycosylation involve defects in the formation or transfer of the lipid-linked oligosaccharide precursor of N-linked glycans. SLC35A2-CDG (previously CDG-IIm) is caused by hemizygous or heterozygous mutations in the X-linked gene SLC35A2 that encodes a UDP-galactose transporter. To date there have only been 10 reported patients with SLC35A2 mutations. Importantly, the patient presented here was not identified in infancy by transferrin isoform analysis, the most common testing to identify patients with a congenital disorder of glycosylation. Case presentation: A 27 month old girl with developmental delay, central hypotonia, cerebral atrophy, and failure to thrive with growth retardation was identified by whole exome sequencing to have a mosaic missense variant in SLC35A2 (c.991G > A). This particular variant has been previously reported in a male as a mutation. Comparison of all clinical findings and new information on growth pattern, growth hormone testing and neurodevelopmental evaluation are detailed on the patient presented. Conclusion: This patient report increases the clinical and scientific knowledge of SLC35A2-CDG, a rare condition. New information on reduced growth, growth hormone sufficiency, lack of seizures, and neurodevelopmental status are presented. This new information will be helpful to clinicians caring for individuals with SLC35A2-CDG. This report also alerts clinicians that transferrin isoform measurements do not identify all patients with congenital disorders of glycosylation.
KW - Congenital disorder of glycosylation
KW - Growth failure
KW - SLC35A2 mutation
KW - Transferrin isoforms
KW - Whole exome sequencing
KW - Inborn errors of metabolism
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U2 - 10.1186/s12881-018-0617-6
DO - 10.1186/s12881-018-0617-6
M3 - Article
C2 - 29907092
AN - SCOPUS:85048608008
SN - 1471-2350
VL - 19
JO - BMC medical genetics
JF - BMC medical genetics
IS - 1
M1 - 100
ER -