Phenotypes Associated with 16p11.2 Copy Number Gains and Losses at a Single Institution.

Chromosome 16p11.2 is one of the susceptible sites for recurrent copy number variations (CNVs) due to flanking near-identical segmental duplications. Five segmental duplications, named breakpoints 1 to 5 (BP1-BP5), have been defined as recombination hotspots within 16p11.2. Common CNVs on 16p11.2 include a proximal ~593 kb between BP4 and BP5, and a distal ~220 kb between BP2 and BP3. We performed a search for patients carrying 16p11.2 CNVs, as detected using chromosome microarray (CMA), in the Molecular Diagnostic Laboratory at the University of Texas Medical Branch (UTMB), in Galveston. From March 2013 through April 2018, a total of 1200 CMA results were generated for germline testing, and 14 patients tested positive for 16p11.2 CNVs, of whom 7 had proximal deletion, 2 had distal deletion, 4 had proximal duplication, and 1 had distal duplication. Herein, we provide detailed phenotype data for these patients. Our study results show that developmental delay, abnormal body weight, behavioral problems, and hypotonia are common phenotypes associated with 16p11.2 CNVs.

Franklin Delano Roosevelt's (FDR's) (1882-1945) 1921 neurological disease revisited; the most likely diagnosis remains Guillain-Barré syndrome.

In 2003, we published evidence that the most likely cause of FDR's 1921 neurological disease was Guillain-Barré syndrome. Afterwards, several historians and neurologists stated in their publications that FDR had paralytic poliomyelitis. However, significant criticism of our article or new support for that diagnosis was not revealed. One critic claimed that FDR's cerebrospinal fluid indicated poliomyelitis, but we did not find evidence that a lumbar puncture was performed. The diagnosis of FDR's neurological disease still depends upon documented clinical abnormalities. His age, prolonged symmetric ascending paralysis, transient numbness, protracted dysaesthesia (pain on slight touch), facial paralysis, bladder and bowel dysfunction, and absence of meningismus are typical of Guillain-Barré syndrome and are inconsistent with paralytic poliomyelitis. FDR's prolonged fever was atypical for both diseases. Finally, permanent paralysis, though commoner in paralytic poliomyelitis, is frequent in Guillain-Barré syndrome. Thus, the clinical findings indicate the most likely diagnosis in FDR's case remains Guillain-Barré syndrome.