A year later - on the anniversary of the deadliest disaster in Turkey's modern history - they are still searching for him.
"If he were alive, he'd find us," Akyuz said in her home in Iskenderun, a Mediterranean port city in Hatay province.
"Everyone has a place to go on Feb. 6. We have nowhere to go. We at least want to find out where he is."
Families with loved ones still missing continue to seek answers from authorities, agonising over what may have happened to them in the wreckage and at hospitals and cemeteries.
One Turkish advocacy group says 140 people are still missing after the quake that killed some 53,000 people in Turkey and another 6,000 in neighbouring Syria.
Akyuz recalled the shock of seeing the unrecognisable rubble at her brother's home when she arrived that morning, eight months pregnant at the time, with her mother, husband and two children.
Thinking he might have been trapped while trying to escape from a terrace, they lifted some collapsed sheet metal - but he was not there.
For eight days the family watched the search operations. But they did not find Gulec, who had studied architecture at Istanbul's Okan University and was working at his family's furniture company in Iskenderun.
Akyuz, 34, a lawyer, said they sought clues in the courthouse, cemetery, and in hospital records and filed a missing person report with the prosecutor's office.
In response to a photograph and notice placed on social media, she received a call one day from a woman claiming to have seen her brother removed from the neighbouring building and placed into a white car.
It rekindled hopes for a time that he may still be alive, she said, but nothing came of it. Now she believes that her brother was buried in either a nameless grave or in someone else's place.
"We did not know what to do. We did not know whom to ask. CCTV footage shows he entered the house, and the phone signal was last detected in the building," she said. "My mother visited intensive care centres, morgues, and cold storage rooms."
'LOOKING FOR HER TEETH'
The 7.8-magnitude earthquake flattened towns and swathes of city centers across a region the size of Belgium and the Netherlands combined.
Selahattin Kaban, head of the Association for Solidarity with Earthquake Victims and Relatives of the Missing (DEMAK), said 140 people, including 38 children, are still missing, including 118 in Hatay, which was the hardest hit region.
"Some were not found in the rubble, some went missing in the hospital," he told Reuters.
Family Minister Mahinur Ozdemir Goktas said in comments televised on Turkish broadcasters in recent days that there are no missing children after the quake. She and other authorities have made no statement about the 140 missing people claimed by DEMAK.
The DEMAK families asked to meet Goktas and have called on parliament to set up an inquiry. "Even if our missing loved ones are dead, we want their graves to be found," Kaban said.
Last month, President Tayyip Erdogan's ruling AK Party and the allied MHP declined to take up a written parliamentary question about missing children from the earthquake that was submitted by the opposition IYI Party.
In Hatay's capital Antakya, Aysun Celenk, 65, tells a similar tale of an endless search for a sibling.
After the quake, she waited next to the pile of rubble where her sister Berna and brother-in-law Kemal Torun had lived on the fourth floor of a seven-storey apartment building on Adnan Menderes Avenue.
She said she did not leave the scene for even a moment, and on the sixth day an excavator arrived, beginning the search for bodies. But neither Berna nor Kemal, both 58-year-old teachers, were found. Nor were there traces of them in a soil survey afterward that she followed closely.
"There was a market below. The generators there exploded. Then the fire started," Celenk said. "Maybe they melted in the fire."
She filed a petition at the prosecutor's office for her relatives and several others she said are still missing from that building, and says she will "pursue it to the end".
She still visits the area at least three times a week. "My sister was everything to me," Celenk said on a recent visit. "Forget about the bones, I am looking for her teeth."
