Table 1.
Etiological Diagnostic Testing for the Proband
| Result | Cost (in US dollars)a | |
|---|---|---|
| Genetic tests (suspected diagnosis) | ||
| Karyotype | 46,XY | 315 |
| Chromosomal microarray | Normal | 2972 |
| FMR1 gene testing (Fragile X syndrome) | Normal | 1414 |
| Deletion/duplication 15q11-q13 (Prader-Willi syndrome) | Negative | 1570 |
| MAGEL2 gene (Prader-Willi syndrome) | Negative | 1575 |
| IKBKAP gene testing (familial dysautonomia) | Normal | 1500 |
| NSD1 gene sequencing (Sotos syndrome) | Negative | 892 |
| CDKN1C, H19, KCNQ1OT1 methylation studies (Beckwith-Wiedeman syndrome) | Negative | 1800 |
| GPC3 gene sequencing (Simpson-Golabi-Behmel syndrome) | Negative | 1000 |
| PTEN gene (Bannayan-Riley-Ruvalcaba syndrome) | Negative | 1768 |
| MECP2 gene (Rett syndrome) | Negative | 1550 |
| PHOX2B gene testing (central hypoventilation) | Negative | 921 |
| Total cost of genetic testing | 17 277 | |
| Clinical whole exome sequencing (2013) | 7000 | |
| Other diagnostic tests | ||
| Urinary organic acids, ammonia, lactate, pyruvate, electrolytes, glucose, uric acid (inborn errors of metabolism, mitochondrial disease) | Normal | 333 |
| Biotinidase enzyme activity (biotinidase deficiency) | Normal | 115 |
| O-glycan profile and quantification (congenital disorders of glycosylation) | Mild changes; repeat, normal | 474 |
| N-glycan and carbohydrate-deficient transferrin (congenital disorders of glycosylation) | Normal | 120 |
| Serum glutaric acid level (glutaric acidemia type 1) | Normal | 169 |
| MRI with magnetic resonance spectroscopy (cerebral creatine deficiency, Canavan disease) | Large subarachnoid space, prominent ventricles | 3272 |
a
Costs are based on the Laboratory Medicine Rate Book at Boston Children's Hospital and are comparable with various commercial laboratories in the United States.