As explained in this eMedTV segment, a mutation in the F8 gene causes hemophilia A, while a mutation in the F9 gene is responsible for hemophilia B. This article covers these genes in more detail and discusses how hemophilia is inherited.
To forward a text message on an iPhone running the iOS 8 operating system, open the conversation thread, select an individual message and then use the Share feature to send the message to one or more of your contacts.
On my Verizon iPhone I press and hold on the message, click more, click the forward icon in the bottom right, type in a contact name (or 10 digit mobile number), then click send. The process should be similar on an android.