Fragile X testing as a second-tier test

Genetic test for fragile X syndrome

Fragile X testing in a diagnostic cytogenetics laboratory.

Chromosome results obtained from 1012 patients referred with developmental delay without known cause within the three years 1985 to 1987 are reported. G banding analysis and assessment of 70 cells for fragile X gave abnormal results in 84 cases: fragile X in 31 patients and other abnormalities in 53 patients. A further 16 sibs expressing the fragile X were detected in family studies originating...

2-tiered antibody testing for early and late Lyme disease using only an immunoglobulin G blot with the addition of a VlsE band as the second-tier test.

BACKGROUND Standard 2-tiered immunoglobulin G (IgG) testing has performed well in late Lyme disease (LD), but IgM testing early in the illness has been problematic. IgG VlsE antibody testing, by itself, improves early sensitivity, but may lower specificity. We studied whether elements of the 2 approaches could be combined to produce a second-tier IgG blot that performs well throughout the infec...

Fragile X testing in obstetrics and gynaecology in Canada.

OBJECTIVE To provide Canadian family physicians, genetic counsellors, medical geneticists, midwives, and obstetrician-gynaecologists with recommendations regarding screening for fragile X in the obstetrical and gynaecological population. METHODS Medline, the Cochrane Library, journals, and textbooks were searched for English-language articles, published between 1966 and March 2008, relating t...

Genetic Testing for FMR1 Mutations (Including Fragile X Syndrome)

Patient Selection Criteria Coverage eligibility will be considered for fragile X mental retardation 1 (FMR1) mutations the following patient populations:  Individuals of either sex with intellectual disability, developmental delay, or autism spectrum disorder (see Policy Guidelines ◊ ).  Prenatal testing of fetuses of known carrier mothers (see Policy Guidelines ◊ ).  Affected individuals or...