The problem is that existing gene therapies for many inherited diseases have worked only partially or not at all.
问题在于，治疗许多遗传疾病的现有基因疗法仅仅部分有效，或者根本无效。
While not usually inherited like the color of hair and eyes, many families hae predispositions for specific diseases and these diseases may affect fertility.
虽然这些疾病不像头发颜色和眼镜颜色那样明显地遗传，但是很多家族都有易患某种疾病的倾向，而这些疾病也是有可能影响生育的。
A baby usually is protected from many diseases for a short time after birth by an immunity inherited from his mother.
婴儿继承母亲的免疫力，出生后不长的一段时间人通常受到保护，不受多种疾病的侵袭。
应用推荐