Blood relations matter in that part of who we are is derived from our family ancestry--that dimple on the chin, those sea green eyes, and etc. Is it important to have relationships with “blood” or family? Not necessarily. Besure says it well--barring medical or legal issues, “family” might be more important than blood.
Blood relations is the modern version of fate: you can't escape it. Your family history is always with you, whether you are raise by them are not. Your past is not even past. The old adages that state you will inevitably raise your children very closely to way you were raised usually bear fruit, despite every young person's denial of it.
It even goes beyond parental imprinting; it's in the blood. Genetic studies bear this out. Identical twins separated at birth have uncannily similar lifestyles. One set in particualr were both firemen; both married wives with the same first name; both drank the same brand of beer; both built the same benches around trees in their back yards.
Original guestimates of the nature v. nurture debate with regard to intelligence used to be split 50% vs. 50%. Now, it's more heavily weighted toward nature. As a teacher who's seen the products of several gene pools across the country, I can attest that genetics is a greater factor in academic performance than the quality of the schools themselves.
Blood relationships are important but that does not necessarily mean that they are positive relationships. I would say that "family" is very important. I have known people who have come from very dysfunctional families but have other relationships with people who are not blood related and those relationships have been stronger.
I would agree with the above poster, blood relatives are important in that they are your ancestry, also they are important in some medical situations. However, in respect to your relationships with them it really does not matter whether they are blood relatives or not.
It depends on what the situation is that you are referring to as to whether or not blood relations are important. If you are discussing the need to know your medical history in order to have a better idea of what risk factors might have an impact on your life, then blood relatives are important because they are the people who determine your genetic structure.
If you are talking about marriage and procreation, then it is a good idea not to closely intermarry within your bloodlines as this can lead to birth defects.
However, if you are referring to the strength of bonds that can be formed, I would argue that blood does not determine family. Adopted children can be as loved by their parents or even more loved than blood children. You can choose your friends and, to a degree, depending on how you look at it, you can choose who you consider as family and those ties can be stringer emotionally than bonds that are shaped purely on genetic factors.
The term "blood relation" refers to family members who have direct biological relationship to one another and can apply to cousins, maternal and paternal aunts and uncles, grandparents, brothers and sisters and biological parents. In this biological sense, "blood relation" is relevant for knowing your family connections, for having closely connected people who comprise your "village" that helps you make your way along the paths of life that require so many unfamiliar decisions, and for feeling like part of something bigger than you are.
There is also a moral sense that is considered in regard to "blood relation" as well, and the moral sense is sometimes not as clear cut and can be a matter of great controversy. Some say that regardless of moral questions, brutality, violence, neglect, illegal actions, molestation, etc., "blood relation" continues to be of utmost importance and needs to be maintained and cultivated.
Others say that moral issues, like those listed above, establish special circumstances wherein "blood relation" becomes a secondary consideration of decreasing value that may even become entirely valueless. Unfortunately, young people and adolescents aren't often in a position to make decisions on their own about stepping away from these kinds of relations, ones that involve moral issues.
But there are options available in that a young person may be able to arrange to talk with and live with a aunt or uncle or grandparent or godmother or godfather or family friend. Talking to aunts and uncles or grandparents, godparents or family friends whom one trusts can help young people and adolescents find alternatives to "blood relations" that are detrimental or dangerous.
In a legal sense, blood relative is the first choice of the courts and agencies to take over care of a child that has been abandoned, abused, neglected or orphaned. Blood relatives in the immediate family are the ones given visitation rights and sometimes decision making power in a medical sense at a doctor's office or hospital.
If you are a minor, blood relations are often allowed to pick you up from school or are where you would spend time when you cannot be supervised by parents.
I guess this really depends on what context you are talking about.
But in general, I do not believe that blood relations are very important. True, we should and we usually do love our close blood relations very much. But that is generally because we grow up with them. An adopted child is most likely going to love their adopted relatives just as much as they would love people who were actually related to them by blood.
Similarly, it is possible to really dislike people even if they are related to you by blood. Hopefully you still care about them, but you don't have to like them.
Already, many posters have given satisfactorily valuable opinions.
Blood relation is definitely important and relevant in many cases. Still there are few cases where blood relation is not essentially relevant. If you want to stand on your own feet with dignity, blood relation can not make you famous or great one. You would require your own effort.
In general belonging to a social groups is essential for happiness of human being. In addition, the institution of family is also very important in cooperative living including taking care of the young ones. Perhaps blood relation is not essential for forming such social groups and families. For example many couples do adopt children.
But blood relation do provide a convenient means of forming close family and extended family which largely consists of blood relations. Further the knowledge of the blood relation, and particularly mothers carrying the young ones in their wombs and giving them birth, does contribute to developing a closer bond between people.
As I see it, it will not be very good to do away with the bonds of relationships created by blood relationships, till some alternate forms of groups to replace families and groups of blood relations are instituted in the society. And I do not see any advantage in doing so. Rather, an exercise of this kind will involve unnecessary and unforeseeable risk to happiness of society.