A 5 year old male patient with a complex phenotype was seen in clinic. He presented with developmental delay, feeding difficulty, cerebellar malformation, coagulation problems, hypothyroidism, retinitis pigmentosa, and bilateral hearing loss. Though not overweight, he also had abnormal distribution of body fat with fat pads in the lower back along with inverted nipples. Testing for congenital disorders of glycosylation (Figure1) showed results consistent with CDG Type I.

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	Adam Guenzel, Ph.D. Resident, Laboratory Genetics and Genomics Mayo Clinic
	Silvia Tortorelli, M.D., Ph.D. Consultant, Laboratory Genetics and Genomics Mayo Clinic Assistant Professor of Laboratory Medicine and Pathology Mayo Clinic College of Medicine and Science