DNA is a really exciting groundbreaker for those of us who are searching. When you find the person that you are searching for, you want to be happy, approachable and NOT CREEPY. 
I may have posted a letter in the past, but as I get good examples, I will continue to share them here for all to use. 
Here is an excellent example of a letter to send to a potential parent or child. 

Feel free to print this and use it for your own personal use. I have made the parts that you replace with your information XXX for easy identification.

Dear XXX,
I believe that we may have something in common. I am doing family research and my leads are all pointing to you as the person who would have the information that I am searching for. 
I was born at XXX hospital in XXX, XXX. I weighed XXX pounds and XXX ounces. I was born at XXX time. My birthdate is XXX. My name at birth was XXX
My parents were very brave because they made an adoption plan for me. I was placed for adoption through XXX adoption agency. 
I was adopted at the age of XXX. My parents XXX and XXX raised me from that age. 
I grew up in the state of XXX. I hope that you will get in touch with me because I am certain that you will have the information I need to complete my search.
I have had DNA testing done through XXX. 
I have enclosed a Self Addressed Stamped Envelope for your convenience. I can also be reached at XXX mobile phone and XXX email address if that is more convenient. 
I look forward to hearing from you. 
Kindest Regards, 
XXX

If you have been diagnosed with bipolar disorder or major depressive disorder, you may qualify for a study through 23 and Me. (Free Kit!)
Here are the criteria that they list through this link: enroll.23andme.com/research/depression-bipolar/identity/
Please check that you meet all criteria below:

1. You are 18-50 years old and live in the United States.
2. You have access to a desktop or laptop computer; smartphones and tablets will not work with this study.
3. You have been diagnosed with major depressive disorder or bipolar disorder.
4. You have been prescribed medication to treat major depressive disorder or bipolar disorder.
5. You are willing to provide a saliva sample for DNA testing.
6. You are willing to complete online study sessions over the course of nine months. Each study session takes between 10-30 minutes and may include surveys and a series of cognitive tests online.
7. You acknowledge that your ability to post on 23andMe community forums will be disabled when you enroll and are accepted into the depression and bipolar study due to a restriction in the study design.

If this fits you or someone that you know, please share this link so that important research can be completed and you will be helping! 
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