Which of the following statements is true about genetic disorders？

A.Carriers with chromosomal balanced translocation generally have no phenotype, but infertility, miscarriage and fetal malformations may occur during childbirth

B.Patients with genetic diseases must have a family history, but no de novo mutation

C.The pathogenic gene of X-linked recessive genetic diseases is located on the X chromosome and is dominant

D.Genetic disease is diagnosed by molecular biology techniques such as microarrays and PCR, through the DNA molecular level

正确答案：Carriers with chromosomal balanced translocation generally have no phenotype, but infertility, miscarriage and fetal malformations may occur during childbirth；Genetic disease is diagnosed by molecular biology techniques such as microarrays and PCR, through the DNA molecular level