The B-1/B-2 visitor visa is for people traveling to the United States temporarily for business (B-1) or for tourism or medical treatment (B-2). In most cases, the B-1 and B-2 visas are combined and issued as one visa: the B-1/B-2. Fees: $160 application fee, reciprocity fees depending on country of citizenship. Russian nationals can receive single or multiple entry visitor visas valid for the period of up to three years, and pay no reciprocity fee.
FISH testing is usually done on the same samples as a karyotype - blood, amniocytes or a chorionic villi sample. A FISH test is done using a fluorescent probe that binds to certain specific chromosomes. These fluorescent probes are made of DNA specific to certain chromosomes and are tagged with a fluorescent dye.
Using the FISH test for 22q11.2, it was discovered that about 95% of patients with DiGeorge syndrome and VCFS have a deletion. This special FISH test for 22q11.2 deletions is available in many clinical laboratories that look at chromosomes (referred to as cytogenetics laboratories).